## Explanation

Minor release of `@metamask/multichain-account-service`.

Changelog:

```md
### Added

- Add per-provider throttling for non-EVM account creation to improve performance on low-end devices ([#7000](#7000))
  - Solana provider is now limited to 3 concurrent account creations by default when creating multichain account groups.
  - Other providers remain unthrottled by default.
```

Mobile test-drive PR:
MetaMask/metamask-mobile#21905 (QA'd ✅ )

## References

<!--
Are there any issues that this pull request is tied to?
Are there other links that reviewers should consult to understand these
changes better?
Are there client or consumer pull requests to adopt any breaking
changes?

For example:

* Fixes #12345
* Related to #67890
-->

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [ ] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Publish @metamask/multichain-account-service 2.1.0 adding per-provider
throttling (Solana capped at 3 concurrent) and update dependents; bump
monorepo to 657.0.0.
> 
> - **multichain-account-service
(`packages/multichain-account-service`)**:
> - Release `2.1.0` with per-provider throttling for non-EVM account
creation.
>     - Solana provider limited to 3 concurrent creations by default.
>   - Update `CHANGELOG.md` and version references.
> - **Dependents**:
> - Bump `@metamask/multichain-account-service` devDependency to
`^2.1.0` in `packages/account-tree-controller` and
`packages/assets-controllers`.
> - **Repo**:
>   - Bump monorepo version to `657.0.0`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
b4773ca. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

…-EVM account creation (#7000)

## Explanation

<!--
Thanks for your contribution! Take a moment to answer these questions so
that reviewers have the information they need to properly understand
your changes:

* What is the current state of things and why does it need to change?
* What is the solution your changes offer and how does it work?
* Are there any changes whose purpose might not obvious to those
unfamiliar with the domain?
* If your primary goal was to update one package but you found you had
to update another one along the way, why did you do so?
* If you had to upgrade a dependency, why did you do so?
-->

## References

Related to
[MUL-1222](https://consensyssoftware.atlassian.net/browse/MUL-1222),
[MUL-1221](https://consensyssoftware.atlassian.net/browse/MUL-1221)

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [ ] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes


[MUL-1222]:
https://consensyssoftware.atlassian.net/browse/MUL-1222?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ


<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adds per-provider concurrency limits for non-EVM account creation
(Solana defaults to 3), refactors creation flow to optionally
await/aggregate errors, and updates providers/tests accordingly.
> 
> - **Core**
> - Introduce `withMaxConcurrency` in `SnapAccountProvider` using a
semaphore; add optional `maxConcurrency` to `SnapAccountProviderConfig`.
> - Add `toRejectedErrorMessage` util and factor non‑EVM creation into
`MultichainAccountWallet.#createNonEvmAccounts`, supporting await-all
with aggregated errors and background mode logging.
> - Forward optional `providerConfigs` safely (`?.`) and allow
Solana-specific config (including `maxConcurrency`).
> - **Providers**
> - Update `SolAccountProvider`, `BtcAccountProvider`, and
`TrxAccountProvider` to use `SnapAccountProviderConfig` and throttle
`createAccounts` via `withMaxConcurrency`.
>   - Default Solana `maxConcurrency: 3`; others unthrottled by default.
> - **Tests**
>   - Add concurrency tests for `SnapAccountProvider`.
> - Update wallet tests to verify aggregated non‑EVM failures when
awaiting all and provider config forwarding.
> - **Docs**
>   - Update `CHANGELOG.md` with new throttling behavior and defaults.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
6e21486. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

[MUL-1221]:
https://consensyssoftware.atlassian.net/browse/MUL-1221?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

## Explanation

Minor release of `@metamask/multichain-account-service`.

Changelog:

```md
### Added

- Add per-provider throttling for non-EVM account creation to improve performance on low-end devices ([#7000](#7000))
  - Solana provider is now limited to 3 concurrent account creations by default when creating multichain account groups.
  - Other providers remain unthrottled by default.
```

Mobile test-drive PR:
MetaMask/metamask-mobile#21905 (QA'd ✅ )

## References

<!--
Are there any issues that this pull request is tied to?
Are there other links that reviewers should consult to understand these
changes better?
Are there client or consumer pull requests to adopt any breaking
changes?

For example:

* Fixes #12345
* Related to #67890
-->

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [ ] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Publish @metamask/multichain-account-service 2.1.0 adding per-provider
throttling (Solana capped at 3 concurrent) and update dependents; bump
monorepo to 657.0.0.
> 
> - **multichain-account-service
(`packages/multichain-account-service`)**:
> - Release `2.1.0` with per-provider throttling for non-EVM account
creation.
>     - Solana provider limited to 3 concurrent creations by default.
>   - Update `CHANGELOG.md` and version references.
> - **Dependents**:
> - Bump `@metamask/multichain-account-service` devDependency to
`^2.1.0` in `packages/account-tree-controller` and
`packages/assets-controllers`.
> - **Repo**:
>   - Bump monorepo version to `657.0.0`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
b4773ca. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

## **Description**

This PR bumps `@metamask/multichain-account-service` to `^2.1.0`, which
includes performance improvements for lower end devices during account
creation. Changelog:

```md
- Add per-provider throttling for non-EVM account creation to improve performance on low-end devices ([#7000](MetaMask/core#7000))
  - Solana provider is now limited to 3 concurrent account creations by default when creating multichain account groups.
  - Other providers remain unthrottled by default.
```

## **Changelog**

<!--
If this PR is not End-User-Facing and should not show up in the
CHANGELOG, you can choose to either:
1. Write `CHANGELOG entry: null`
2. Label with `no-changelog`

If this PR is End-User-Facing, please write a short User-Facing
description in the past tense like:
`CHANGELOG entry: Added a new tab for users to see their NFTs`
`CHANGELOG entry: Fixed a bug that was causing some NFTs to flicker`

(This helps the Release Engineer do their job more quickly and
accurately)
-->

CHANGELOG entry: null

## **Related issues**

Fixes: https://consensyssoftware.atlassian.net/browse/MUL-1230

## **Manual testing steps**

```gherkin
Feature: my feature name

  Scenario: user [verb for user action]
    Given [describe expected initial app state]

    When user [verb for user action]
    Then [describe expected outcome]
```

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

<!-- [screenshots/recordings] -->

### **After**

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

- [x] I’ve followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I’ve included tests if applicable
- [x] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [x] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [x] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Updates `@metamask/multichain-account-service` from `^2.0.1` to
`^2.1.0`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
c10179c. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

## **Description**

This PR bumps `@metamask/multichain-account-service` to `^2.1.0`, which
includes performance improvements for lower end devices during account
creation. Changelog:

```md
- Add per-provider throttling for non-EVM account creation to improve performance on low-end devices ([#7000](MetaMask/core#7000))
  - Solana provider is now limited to 3 concurrent account creations by default when creating multichain account groups.
  - Other providers remain unthrottled by default.
```

[![Open in GitHub
Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/MetaMask/metamask-extension/pull/37481?quickstart=1)

## **Changelog**

<!--
If this PR is not End-User-Facing and should not show up in the
CHANGELOG, you can choose to either:
1. Write `CHANGELOG entry: null`
2. Label with `no-changelog`

If this PR is End-User-Facing, please write a short User-Facing
description in the past tense like:
`CHANGELOG entry: Added a new tab for users to see their NFTs`
`CHANGELOG entry: Fixed a bug that was causing some NFTs to flicker`

(This helps the Release Engineer do their job more quickly and
accurately)
-->

CHANGELOG entry: null

## **Related issues**

Fixes: https://consensyssoftware.atlassian.net/browse/MUL-1230

## **Manual testing steps**

1. Go to this page...
2.
3.

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

<!-- [screenshots/recordings] -->

### **After**

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I’ve included tests if applicable
- [x] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [x] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [x] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

## **Description**

This PR bumps `@metamask/multichain-account-service` to `^2.1.0`, which
includes performance improvements for lower end devices during account
creation. Changelog:

```md
- Add per-provider throttling for non-EVM account creation to improve performance on low-end devices ([#7000](MetaMask/core#7000))
  - Solana provider is now limited to 3 concurrent account creations by default when creating multichain account groups.
  - Other providers remain unthrottled by default.
```

[![Open in GitHub
Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/MetaMask/metamask-extension/pull/37481?quickstart=1)

## **Changelog**

<!--
If this PR is not End-User-Facing and should not show up in the
CHANGELOG, you can choose to either:
1. Write `CHANGELOG entry: null`
2. Label with `no-changelog`

If this PR is End-User-Facing, please write a short User-Facing
description in the past tense like:
`CHANGELOG entry: Added a new tab for users to see their NFTs`
`CHANGELOG entry: Fixed a bug that was causing some NFTs to flicker`

(This helps the Release Engineer do their job more quickly and
accurately)
-->

CHANGELOG entry: null

## **Related issues**

Fixes: https://consensyssoftware.atlassian.net/browse/MUL-1230

## **Manual testing steps**

1. Go to this page...
2.
3.

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

<!-- [screenshots/recordings] -->

### **After**

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I’ve included tests if applicable
- [x] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [x] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [x] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

## **Description**

This PR bumps `@metamask/multichain-account-service` to `^2.1.0`, which
includes performance improvements for lower end devices during account
creation. Changelog:

```md
- Add per-provider throttling for non-EVM account creation to improve performance on low-end devices ([#7000](MetaMask/core#7000))
  - Solana provider is now limited to 3 concurrent account creations by default when creating multichain account groups.
  - Other providers remain unthrottled by default.
```

[![Open in GitHub
Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/MetaMask/metamask-extension/pull/37481?quickstart=1)

## **Changelog**

<!--
If this PR is not End-User-Facing and should not show up in the
CHANGELOG, you can choose to either:
1. Write `CHANGELOG entry: null`
2. Label with `no-changelog`

If this PR is End-User-Facing, please write a short User-Facing
description in the past tense like:
`CHANGELOG entry: Added a new tab for users to see their NFTs`
`CHANGELOG entry: Fixed a bug that was causing some NFTs to flicker`

(This helps the Release Engineer do their job more quickly and
accurately)
-->

CHANGELOG entry: null

## **Related issues**

Fixes: https://consensyssoftware.atlassian.net/browse/MUL-1230

## **Manual testing steps**

1. Go to this page...
2.
3.

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

<!-- [screenshots/recordings] -->

### **After**

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I’ve included tests if applicable
- [x] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [x] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [x] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.