Support ServerMetaData in CreateAgent AgentInfo

[dwkang]

Summary

Add AgentInfo server metadata support through CreateAgent and send runtime config metadata in service_info.

Scope

• Extend CreateAgent to accept ServerMetaData with optional args and libs.
• Default server_info to "C/C++ Application" when ServerMetaData is not provided.
• Send non-default runtime config entries through service_info instead of vmarg.
• Keep config metadata included in service_info for all AgentInfo registrations.
• Remove obsolete SetAppMetaData/setServerMetaData paths from AgentImpl and reload handling.

Validation

• cmake --build --preset debug-cached
• ctest --test-dir build/debug-cached --output-on-failure