chore: checkpoint web Blender feature-gap work, docs and tests

- update native web_engine sources and rebuilt wasm artifacts
- add task cards, status notes and tooling scripts
- add web e2e specs, tutorial UI sources and tutorial assets
- sync golden task manifests and audit records

Co-Authored-By: Claude Code <noreply@anthropic.com>

tests/golden/WBV2/continuous-supervisor.json

@@ -1,19 +1,17 @@
 {
   "schemaVersion": 1,
-  "pid": null,
-  "updatedAt": "2026-09-03T01:03:00.000Z",
+  "pid": 2773706,
+  "updatedAt": "2026-09-05T10:25:46.735Z",
   "state": "complete",
   "iteration": 1,
   "before": {
-    "task": "WBV2-P1145-001",
-    "parentManifest": "tests/golden/WBV2-P1145-000/manifest.json"
+    "task": "WBV2-P1419-001",
+    "parentManifest": "tests/golden/WBV2-P1419-000/manifest.json"
   },
   "after": {
-    "task": "WBV2-P1145-001",
-    "parentManifest": "tests/golden/WBV2-P1145-000/manifest.json"
+    "task": "WBV2-P1419-001",
+    "parentManifest": "tests/golden/WBV2-P1419-000/manifest.json"
   },
-  "reason": "terminal_plan_and_remote_verified",
   "childExit": 0,
-  "remoteHeadVerified": true,
-  "localHead": "1fa1b51f58e3f9a7d20bcc229f8d9fa7a685ba92"
+  "reason": "terminal_module_complete"
 }