feat(mma): Complete Visual DAG implementation, fix link creation/deletion, and sync docs

conductor/tracks/minimax_provider_20260306/metadata.json

@@ -0,0 +1,10 @@
+{
+  "id": "minimax_provider_20260306",
+  "title": "MiniMax Provider Integration",
+  "description": "Add MiniMax as a new AI provider with M2.5, M2.1, M2 models",
+  "type": "feature",
+  "status": "new",
+  "created_at": "2026-03-06",
+  "priority": "high",
+  "owner": "tier2-tech-lead"
+}