Address review feedback: Add JavaDoc, fix typo, wire up leak detection

[Copilot]

Description

Addresses review feedback on leak detection infrastructure PR. Issues resolved:

1. Added comprehensive JavaDoc to StackTraceUtil - Documents purpose (diagnostic stack trace capture), performance implications, and thread-safety guarantees.

2. Fixed typo in RxDocumentClientImpl - "teh" → "the" in JavaDoc.

3. Wired up client leak detection lifecycle hook in close() method:

   • Call removeFromActiveClients() at start of close() before resource cleanup
   • The corresponding addToActiveClients() call is already in the constructor (line 517)
   • Enables tracking of active clients when COSMOS.CLIENT_LEAK_DETECTION_ENABLED is set

4. Removed redundant addToActiveClients() call - Duplicate call in init() method was removed after merge, keeping only the constructor call (line 517).

Without these changes, the activeClients map would not be properly maintained and leak detection would be non-functional.

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

General Guidelines and Best Practices

• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[FabianMeiswinkel]

see comments

[FabianMeiswinkel]

@copilot I think we can close the PR because no more changes are left?

[Copilot]

@copilot I think we can close the PR because no more changes are left?

Yes, all review feedback has been addressed and all changes are complete. The PR is ready to close.

[FabianMeiswinkel]

No changes left