chore: adapt deployment section to changed spec

discovery/README.md

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+# Discovery of DSP endpoints in Practice
+
+Participants usually require their endpoints to be protected and publicly reachable. Clients (usually
+Consumers) have an interest to automatically discover DSP-endpoints and infer knowledge about their expected behavior.
+For this, the [metadata endpoint](https://eclipse-dataspace-protocol-base.github.io/DataspaceProtocol/2025-1-RC4/#exposure-of-dataspace-protocol-versions) 
+is particularly relevant because it hints to the Consumer what version of the DSP and profiles to expect, allowing the 
+Consumer to terminate the interaction early if there's no commonly understood protocol.
+
+Deployment of endpoints is a detail that is at the discretion of each participant. That's why it's necessary to
+differentiate URLs and their relationship with each other.
+
+- `<domain>` is the naked domain without URL segments or fragments.
+- `<root>` is the URL on which the `/.well-known/dspace-version` endpoint is hosted. It should be equivalent to 
+`<domain>` to satisfy RFC8615. If it does, clients can always find the metadata endpoint. Else, a Dataspace should
+have conventions to enable discovery of that endpoint in a different manner - for instance by [registering a 
+`DataService`](https://eclipse-dataspace-protocol-base.github.io/DataspaceProtocol/2025-1-RC4/#example-data-service-did-service-example) 
+in their did document.
+- `<base>` is the URL on which the protocol endpoints are hosted. These endpoints host specific profiles and versions
+of the DSP. They are constructable from the metadata endpoint by concatenating `<root>` with the `path` property fetched
+from the document.
+
+A DSP-endpoint must be self-aware of its exposure location, because it needs to send protocol messages that include its
+own callback endpoints. Examples are the `ContractRequestMessage`'s `callbackAddress` property and the `endpointURL`
+the `DataService` exposes. Both serve the `<base>` URL of the relevant services. In deployment scenarios where the
+DSP-endpoints are proxied through the network, the application logic must be made aware of this as it impacts the
+payloads it will emit.