fix: return client error for payload size limit violations

[alepane21]

Return a client error instead of a connect error.

Summary by CodeRabbit

• Refactor
  • Improved error handling for persisted operations publishing to use consistent, structured error responses instead of exceptions for validation, authentication, and storage failures.

Checklist

• I have discussed my proposed changes in an issue and have received approval to proceed.
• I have followed the coding standards of the project.
• Tests or benchmarks have been added or updated.
• Documentation has been updated on https://github.com/wundergraph/cosmo-docs.
• I have read the Contributors Guide.

[coderabbitai]

Walkthrough

The PR converts exception-based error handling in the publishPersistedOperations function to structured response objects. Multiple error paths now return response envelopes with EnumStatusCode and details instead of throwing ConnectError exceptions.

Changes

Cohort / File(s)	Summary
Error handling refactor controlplane/src/core/bufservices/persisted-operation/publishPersistedOperations.ts, controlplane/test/persisted-operations.test.ts	Replaced exception-based error handling (ConnectError, ResourceExhausted) with structured response envelopes across multiple error paths including payload size, authentication, validation, and storage failures. Removed ConnectError and Code imports. Updated test to assert response codes and details instead of catching exceptions.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• fix: encode and validate client name #2124: Directly overlaps with this PR by modifying publishPersistedOperations.ts to change error-handling paths from exceptions to structured response objects, including clientName validation adjustments.
• feat: max number of persistent operations per request #2477: Related to the "payload too large" error handling logic in publishPersistedOperations.ts; this PR replaces ConnectError exception flow with structured ERR responses while the other PR enforces MAX_PERSISTED_OPERATIONS limit.

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: converting payload size limit violations from exceptions to structured client error responses.

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✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 63.59%. Comparing base (59c3b86) to head (405edc9).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2560      +/-   ##
==========================================
- Coverage   63.59%   63.59%   -0.01%     
==========================================
  Files         298      298              
  Lines       41917    41920       +3     
  Branches     4439     4439              
==========================================
  Hits        26657    26657              
- Misses      15238    15241       +3     
  Partials       22       22              

Files with missing lines	Coverage Δ
.../persisted-operation/publishPersistedOperations.ts	64.28% <100.00%> (+0.51%)	⬆️

... and 1 file with indirect coverage changes

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[StarpTech]

LGTM