storcon: port hadron persistence changes

[VladLazar]

Summary of changes

• Some extra persistence methods operating on both new and old tables
  • Ported a bunch of struct stubs for this
• Connection set-up change -- looks like a strict improvement to me
• Made some database knobs configurable -- defaults are from the neon env

[github-actions]

9075 tests run: 8413 passed, 0 failed, 662 skipped (full report)

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Flaky tests (1)

Postgres 17

• test_migration_to_cold_secondary: release-arm64-with-lfc

Code coverage* (full report)

• functions: 34.6% (8831 of 25548 functions)
• lines: 45.6% (71596 of 156860 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
950df26 at 2025-07-30T16:41:48.237Z :recycle:}