- Created TraceContext struct for distributed tracing
- Implemented W3C Trace Context format support (traceparent header)
- Added backward compatibility with legacy X-Trace-ID and X-Span-ID headers
- Created HTTPClientWithTracing for automatic trace propagation in outgoing requests
- Enhanced Tracing middleware to use new trace context system
- Added context propagation helpers (WithTraceContext, FromContext)
- Added child span creation for nested operations
- Comprehensive unit tests for trace context and HTTP client
Phase: PHASE-6
Priority: P2
Progress: 114/267 (42.70%)
