Add Swift module cache to .gitignore

- Added .swift-module-cache/ to .gitignore to prevent Swift compiler cache from being tracked
- Removed existing .swift-module-cache directory from repository
- This cache directory is generated during Swift compilation and should not be version controlled

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: fatbobman

.gitignore

@@ -46,4 +46,7 @@ fastlane/screenshots/**/*.png
 fastlane/test_output
 
 # SwiftUI Previews
-.swiftpm/xcode/
+.swiftpm/xcode/
+
+# Swift Module Cache
+.swift-module-cache/