feat: maximize sorter demo realism and add safe agent MVP

Wire live classifyItem into continuous playback, add jam/E-stop cases,
presenter controls (seek/speed/hotkeys), quality modes, demo scripts,
audit docs, and a verify-only autonomous agent CLI with hard safety limits.

Co-authored-by: Cursor <cursoragent@cursor.com>

package.json

@@ -7,7 +7,13 @@
     "dev": "vite --host 127.0.0.1 --port 3100",
     "build": "tsc -b && vite build",
     "preview": "vite preview --host 127.0.0.1 --port 3100",
-    "test": "vitest run"
+    "test": "vitest run",
+    "agent:dry-run": "node agent/cli.mjs dry-run",
+    "agent:run-once": "node agent/cli.mjs run-once",
+    "agent:status": "node agent/cli.mjs status",
+    "demo:start": "bash scripts/demo-start.sh",
+    "demo:stop": "bash scripts/demo-stop.sh",
+    "demo:health": "bash scripts/demo-health.sh"
   },
   "dependencies": {
     "@react-three/drei": "^10.7.7",