- Rename internal symbol maps to persistent maps (internal_class_map to
persistent_class_map, etc.)
- Replace process-level stable symbol caching with module lifecycle
persistent caching
- Implement lazy initialization of persistent caches after PHP startup
- Add support for built-in class property resolution via reflection
- Remove dynamic property map as all cached properties are module-stable
- Update cache initialization to use atomic operations for ZTS safety
- Modify RSHUTDOWN cleanup to only clear user-defined caches
- Add test coverage for persistent symbol cache behavior
- Update GCC backend to hide extension symbols by default with -fvisibility=hidden
