feat(nodes): live CPU/RAM/disk monitoring in the node list

- node-agent: internal/metrics — read CPU% (GetSystemTimes), RAM (GlobalMemoryStatusEx),
  disk used%/total (GetDiskFreeSpaceEx) via stdlib kernel32 (no external dep; windows
  build + non-windows stub). Heartbeat now reports cpu_pct/ram_available_mb/disk_used_pct/
  disk_total_gb + ae_running.
- render-svc: heartbeat persists last_disk_pct + disk_total_gb (migration 29); RenderNode
  model + node SELECT/scan carry them.
- admin: rewrite NodesTable to the real RenderNode shape (fixes a pre-existing items/V2Node
  mismatch that left the list empty) + a CPU/RAM/disk bars column + stale-heartbeat flag.
- assets-bundle ingestion: ProjectMediaBundle (jszip) auto-maps project.zip → project/scene
  image/demo/colour + music; PatchProject gains image/full_demo/shared_colors_svg.
- scan: RGBA (4-number) colours recognised + frshare single-int controls detected.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

package.json

@@ -32,6 +32,7 @@
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
     "framer-motion": "^12.39.0",
+    "jszip": "^3.10.1",
     "konva": "^9.3.22",
     "lucide-react": "^1.16.0",
     "next": "14.2.35",