feat(logging): add logging standards documentation and improve test c…

[xtrial01]

Closes #536

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Summary

This PR completes the logging infrastructure by adding comprehensive documentation and expanding unit test coverage for the logging module.

Changes

• Added docs/LOGGING_STANDARDS.md with:

  • Logging architecture overview
  • Configuration and usage guidelines
  • Structured logging format
  • Correlation ID handling
  • Sensitive data masking practices
  • Best practices and troubleshooting

• Enhanced logger.service.spec.ts to improve test coverage for:

  • Log levels
  • Structured logging output
  • Correlation ID propagation
  • HTTP logging helpers
  • Error handling
  • Logger configuration

Acceptance Criteria

• ✅ Logger service documented
• ✅ Structured logging documented
• ✅ Log level usage covered by tests
• ✅ Sensitive data masking validated
• ✅ Correlation ID behavior verified
• ✅ Logger configuration documented
• ✅ Unit tests expanded for logging functionality

Testing

• Added and updated unit tests for the logging service.
• Verified all logging functionality behaves as expected.

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[RUKAYAT-CODER]

Well done on the job done so far!
Kindly fix workflow to pass

[xtrial01]

Well done on the job done so far! Kindly fix workflow to pass

Alright on it