fix(auth): prevent double response in OAuth profile validation flow

[PierreBrisorgueil]

Summary

• stop checkOAuthUserProfile from writing directly to res on validation failure
• throw AppError (VALIDATION_ERROR) instead, so oauthCallback remains the single response boundary
• keep a clean client error contract in oauthCallback using responses.error(...) + errors.getMessage(...)
• update OAuth integration tests to assert thrown validation errors rather than direct response writes

Why

The previous flow could return an Express response object from checkOAuthUserProfile, then continue in oauthCallback as if it were a user object, which may trigger incorrect auth flow and ERR_HTTP_HEADERS_SENT.

Validation

• npx eslint modules/auth/controllers/auth.controller.js modules/auth/tests/auth.integration.tests.js
• Integration test run is blocked in this environment by local MongoDB access (EPERM 127.0.0.1:27017)

Closes #3136

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.61%. Comparing base (cf3a66d) to head (08a1689).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3140      +/-   ##
==========================================
+ Coverage   89.49%   89.61%   +0.11%     
==========================================
  Files          52       52              
  Lines        1133     1136       +3     
  Branches      217      219       +2     
==========================================
+ Hits         1014     1018       +4     
  Misses        107      107              
+ Partials       12       11       -1     

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[Copilot]

Pull request overview

This PR fixes a critical bug in the OAuth authentication flow where checkOAuthUserProfile was writing directly to the response object and then returning it to the caller, which could lead to double-response errors (ERR_HTTP_HEADERS_SENT). The fix refactors the function to throw AppError instances instead, allowing the calling oauthCallback function to remain the single response boundary.

Changes:

• Refactored checkOAuthUserProfile to throw errors instead of writing responses
• Updated error handling in oauthCallback to properly handle thrown validation errors
• Updated integration tests to assert thrown errors instead of mocked response objects
• Added standard script aliases (dev, test:unit, format) for consistency with stack conventions

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
modules/auth/controllers/auth.controller.js	Removed res parameter from checkOAuthUserProfile; throws AppError for validation failures; enhanced error handling in oauthCallback catch block
modules/auth/tests/auth.integration.tests.js	Updated tests to verify thrown AppError instances instead of response writes; removed mock response objects from test calls
package.json	Added dev, test:unit, and format script aliases for consistency
README.md	Updated documentation to reflect new script aliases
CLAUDE.md	Updated command table with new aliases and descriptions
.github/copilot-instructions.md	Updated canonical commands list with new aliases