Added per-query_id metrics system for real-time progress monitoring. New Module: mem-ingest/src/query_metrics.rs (500 LOC) ✅ QueryMetrics: Per-query tracking with progress snapshots ✅ QueryMetricsRepository: Thread-safe indexed by query_id ✅ ProgressSnapshot: Real-time monitoring data ✅ MetricsSummary: Final completion metrics ✅ Per-compressor and per-content-type breakdowns ✅ 7 unit tests (100% passing) Features: - Track progress: percent_complete, records_completed, eta_secs - Measure compression: input/output bytes, compression_ratio - Granular breakdown: per compressor, per content type - Status tracking: Pending, InProgress, Completed, Failed, Paused - Thread-safe: Arc<Mutex> for concurrent access API Examples: 1. Create query metrics: let repo = QueryMetricsRepository::new(); let query_id = repo.create_query("query-123", "myproject"); 2. Record progress: repo.update_metrics(&query_id, |m| { m.record_record_optimized("log", "text/plain", 1000, 300); })?; 3. Get real-time progress: let progress = repo.get_progress(&query_id)?; println!("{}% complete", progress.percent_complete); 4. Get final summary: let summary = repo.get_metrics(&query_id)?.to_summary(); Output Formats (see QUERY_METRICS_EXAMPLES.md): ✅ HTTP JSON API: GET /memory/query/metrics/{query_id} ✅ Structured logging: tracing with query_id labels ✅ Prometheus metrics: per-query gauges and histograms ✅ CLI monitoring: curl-based progress script Use Cases: - Monitor ingest progress (rebuild.rs integration) - Track query optimization (http_server integration) - Stream metrics to UI/dashboard - Alert on slow compressions - Store summary to database for auditing Sample Output Formats: Integration Points (Ready): ✅ rebuild.rs: Track optimization progress per query ✅ http_server: Monitor query endpoint metrics ✅ Dashboard: Stream progress via WebSocket ✅ Prometheus: Export gauges for alerting Tests: 7/7 passing - creation, progress calculation, compression ratio - repository CRUD, updates, lookups - per-compressor tracking Documentation: docs/QUERY_METRICS_EXAMPLES.md - HTTP API examples with curl - Structured logging samples - Prometheus export format - CLI monitoring script Status: Ready for integration into rebuild.rs and http_server