🧪 [testing improvement description] Add tests for is_overlay_file and improve extension matching

[ffalcinelli]

🧪 [testing improvement description] Add tests for is_overlay_file and improve extension matching

🎯 What: The testing gap addressed was the lack of comprehensive tests for is_overlay_file logic in src/utils/yaml.rs. The logic also only supported .yaml extensions and not .yml.

📊 Coverage: What scenarios are now tested:

• Exact profile matches (e.g., role.prod.yaml with Some("prod"))
• Generic overlay matches (e.g., client.test.yaml with Some("prod"))
• No profile matches (e.g., my.resource.yaml with None)
• Non-overlays (e.g., role.yaml, .hidden.yaml, missing extensions, single dots).
• Full support for both .yaml and .yml extensions.

✨ Result: The improvement in test coverage provides robust validation for overlay file matching logic. Furthermore, the updated extension logic now cleanly handles .yml alongside .yaml, and ignores hidden files (like .hidden.yaml).

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PR created automatically by Jules for task 16228419180396298649 started by @ffalcinelli

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.55%. Comparing base (3d02386) to head (91eedd9).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #140      +/-   ##
==========================================
+ Coverage   92.54%   92.55%   +0.01%     
==========================================
  Files          27       27              
  Lines        2227     2231       +4     
==========================================
+ Hits         2061     2065       +4     
  Misses        166      166              

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