refactor: Update .gitignore and enhance error handling in feature-loader

Changes:
- Removed specific compiled file patterns from .gitignore to simplify ignore rules.
- Modified error handling in feature-loader.ts to rethrow errors instead of keeping original paths, preventing potential broken references.
- Added ".js" extensions to import statements in types package for ESM compliance.

Benefits:
✅ Cleaner .gitignore for better maintainability
✅ Improved error handling logic in feature-loader
✅ Consistent import paths for ESM compatibility

All tests passing.

.gitignore

@@ -76,14 +76,6 @@ blob-report/
 # TypeScript
 *.tsbuildinfo
 
-# Prevent compiled files in source directories
-libs/*/src/**/*.js
-libs/*/src/**/*.d.ts
-libs/*/src/**/*.d.ts.map
-apps/*/src/**/*.js
-apps/*/src/**/*.d.ts
-apps/*/src/**/*.d.ts.map
-
 # Misc
 *.pem