Build: Windows Portable-Build (§30.2) + Frontend-Tests (§17.10)

- build_portable.sh: Nuitka Onefolder (ADR-0005), 5 Schritte:
  uv sync -> Frontend -> Rust (cargo optional) -> Nuitka ->
  GStreamer-Buendelung + portable Struktur + SHA-256 + ZIP
- Portable Struktur (§9): PORTABLE_MODE, runtime/gstreamer, web/,
  plugins/, projects/, media/, userdata/, config/, logs/, licenses/
- Frontend-Tests: Vitest + Testing Library, 9 Tests:
  LayerTable (10 Spalten, Selektion, 7 Zustaende, Screen-Reader),
  StatusBar (FPS 2 Dezimalstellen, Quality Auto, Art-Net-Status)
- Gesamtsuite 595 Python + 9 Vitest gruen

apps/web/package.json

@@ -6,17 +6,22 @@
   "scripts": {
     "dev": "vite",
     "build": "tsc -b && vite build",
-    "preview": "vite preview"
+    "preview": "vite preview",
+    "test": "vitest run"
   },
   "dependencies": {
     "react": "^19.3.0",
     "react-dom": "^19.3.0"
   },
   "devDependencies": {
+    "@testing-library/jest-dom": "^7.0.1",
+    "@testing-library/react": "^16.3.3",
     "@types/react": "^19.3.0",
     "@types/react-dom": "^19.3.0",
     "@vitejs/plugin-react": "^6.1.1",
+    "jsdom": "^30.0.1",
     "typescript": "^7.0.2",
-    "vite": "^8.2.2"
+    "vite": "^8.2.2",
+    "vitest": "^5.0.0"
   }
 }