Agent Skills: memory-leak-detection

Detect and fix NAPI memory leaks in OpenHarmony Ability Runtime. Use when reviewing NAPI code for memory leaks, especially functions that: (1) Return napi_value, (2) Have napi_value& parameters, (3) Call napi_create_* functions, (4) Set properties with temporary napi_value variables, (5) Work in async callbacks. See references/background.md for detailed memory management principles.