lingniu-vehicle-ingest/.superpowers/sdd/task-4-report.md

Status: Completed Task 4. Commit: 821ea8e39 (feat(stats): write realtime mileage candidates). Test Summary: go test ./internal/stats -run TestWriterAppendWritesSourceCandidateAndProjection -count=1 (PASS) and go test ./internal/stats -count=1 (PASS). Concerns: Writer.Append now always runs projector projection per sample event, even when source identity is unavailable; this preserves final row refresh behavior and matches existing schema flow. Files changed: go/vehicle-gateway/internal/stats/daily_metric.go, go/vehicle-gateway/internal/stats/daily_metric_test.go. Report path: .superpowers/sdd/task-4-report.md.