test(webapp): replace slow metadata replica guard with unit test

[carderne]

Summary

Keeps regression coverage for metadata reads recovering from replica and buffer misses without starting two PostgreSQL containers.

Design

The route test now stubs its three read sources and asserts fallback ordering, the primary result response, and the 404 when all sources miss. Real primary and replica routing remains covered by the run-store integration tests.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 9ea3de8

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[coderabbitai]

Walkthrough

The metadata route test was converted from a Postgres-backed integration test to a mocked loader test. It now mocks authentication, database, run-store, mollifier, and realtime dependencies, initializes default replica and buffer misses, and invokes the loader directly. Assertions verify lookup arguments and ordering, primary recovery with a 200 metadata response, and the missing-run 404 response.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description is missing the required template sections, including Closes #issue, checklist items, Testing steps, Changelog, and Screenshots.	Add the missing template sections: issue reference, checklist, testing steps, changelog, and screenshots or a clear note if none are needed.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly summarizes the main change: replacing the slow metadata replica guard with a unit test.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch test/webapp-fast-metadata-replica-guard

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[devin-ai-integration]

Devin Review found 1 potential issue.