feat: add UnityFramework pod library

- Add UnityFramework.framework with iOS 13.0+ support
- Configure podspec with proper dependencies and xcconfig
- Add EXCLUDED_ARCHS for simulator compatibility
- Include all Unity data and resources

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

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

UnityLibrary/UnityFramework.framework/Modules/module.modulemap

@@ -0,0 +1,6 @@
+framework module UnityFramework {
+  umbrella header "UnityFramework.h"
+  export *
+
+  module * { export * }
+}