trace_region on Android and Windows

[ryantrem]

This pull request implements platform-specific trace_region classes for Android and Windows, providing cross-platform tracing support for performance analysis. Each implementation uses the native tracing APIs on its platform (Android NDK ATrace, Apple os_signpost, Windows ETW TraceLogging) and ensures that trace regions can be correlated across threads and viewed in their respective profiling tools. The changes also improve move semantics, logging, and runtime feature detection.

Platform-specific tracing implementations:

• Android (Source/Android/arcana/tracing/trace_region.h):
  • Implements trace_region using the NDK ATrace async API, supporting cross-thread trace regions and runtime detection of async tracing support for devices below API 29. Logging to logcat is enabled at the log trace level. [1] [2]

• Apple (Source/Apple/arcana/tracing/trace_region.h):

  • Implements trace_region using os_signpost, with detailed instructions for capturing and viewing traces in Instruments. Supports cross-thread correlation using unique os_signpost_id_t.

• Windows (Source/Windows/arcana/tracing/trace_region.h):

  • Implements trace_region using ETW TraceLogging, emitting activity start/stop pairs with unique GUIDs for cross-thread correlation. Provides instructions for capturing and analyzing traces with WPA or PerfView. Debug logging is sent to OutputDebugStringA.

Improvements to trace_region API and semantics:

• Adds move constructor and move assignment operator to trace_region, ensuring safe transfer of region ownership without emitting duplicate end events. [1] [2]
• Stores region name as std::string to ensure correct lifetime and matching for begin/end events across threads. [1] [2]

Runtime and logging enhancements:

• Enables or disables tracing and logging at runtime via static methods, with logging output directed to platform-appropriate sinks (logcat, OutputDebugStringA). [1] [2]
• On Android, resolves async trace functions at runtime using dlsym for compatibility with older devices.

These changes provide robust, cross-platform tracing primitives that integrate with each platform's native profiling tools, improving the ability to analyze and debug performance issues.