feat: Phase 2.6 edges migration to Qdrant (TKG-only architecture)

Phase 2.6.1: co_occurrence_edges migration
- build_co_occurrence_edges_from_qdrant()
- Qdrant embeddings → frame grouping → YOLO objects
- Result: 6679 edges (vs 6701 PostgreSQL)

Phase 2.6.2: face_face_edges migration
- build_face_face_edges_from_qdrant()
- Qdrant embeddings → frame grouping → face pairs
- mutual_gaze detection preserved
- Result: 6 edges (exact match)

Phase 2.6.3: speaker_face_edges migration
- build_speaker_face_edges_from_qdrant()
- Qdrant embeddings → trace_id frame ranges
- SPEAKS_AS edge creation

Architecture:
- All edges use Qdrant payload (no face_detections queries)
- PostgreSQL fallback for empty Qdrant
- Estimated 3.6x performance improvement

Testing:
- Playground (3003): ✓ All Phase 2.6 logs verified
- Edge counts: ✓ Close match with PostgreSQL
- Fallback: ✓ Working

Docs:
- docs_v1.0/DESIGN/TKG_PHASE2_6_EDGES_MIGRATION.md
- docs_v1.0/M4_workspace/2026-06-21_phase2_6_test.md

docs_v1.0/doc_wasm/index.html

@@ -67,6 +67,9 @@ const MODULES = [
   ["12_agent","智慧代理","AI Agents"],
   ["13_config","系統設定","System Config"],
   ["14_identity_history","操作歷史","Operation History (Undo/Redo)"],
+  ["15_tkg","時序知識圖譜","Temporal Knowledge Graph"],
+  ["16_workspace","工作區管理","Workspace Checkin/Checkout"],
+  ["99_incomplete","未完成項目","Incomplete / Undocumented APIs"],
 ];
 
 const el = document.getElementById('content');