chore: update build config, linting, and add test infrastructure

Replace install -D with mkdir -p + install for macOS portability,
add vitest with jsdom and testing-library, configure eslint for
react-hooks v7 warnings, and add tokio test deps for Rust.

package.json

@@ -8,6 +8,8 @@
     "build": "tsc -b && vite build",
     "lint": "eslint .",
     "preview": "vite preview",
+    "test": "vitest run",
+    "test:watch": "vitest",
     "tauri": "tauri"
   },
   "dependencies": {
@@ -18,9 +20,9 @@
     "@tauri-apps/api": "^2.10.1",
     "@tauri-apps/plugin-dialog": "^2.6.0",
     "@tauri-apps/plugin-shell": "^2.3.5",
-    "@types/dagre": "^0.7.53",
+    "@types/dagre": "^0.7.54",
     "@uiw/react-codemirror": "^4.25.4",
-    "@xyflow/react": "^12.10.0",
+    "@xyflow/react": "^12.10.2",
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
     "cmdk": "^1.1.1",
@@ -40,6 +42,8 @@
     "@eslint/js": "^9.39.1",
     "@tailwindcss/vite": "^4.1.18",
     "@tauri-apps/cli": "^2.10.0",
+    "@testing-library/jest-dom": "^6.9.1",
+    "@testing-library/react": "^16.3.2",
     "@types/node": "^24.10.1",
     "@types/react": "^19.2.7",
     "@types/react-dom": "^19.2.3",
@@ -48,11 +52,13 @@
     "eslint-plugin-react-hooks": "^7.0.1",
     "eslint-plugin-react-refresh": "^0.4.24",
     "globals": "^16.5.0",
+    "jsdom": "^28.1.0",
     "shadcn": "^3.8.4",
     "tailwindcss": "^4.1.18",
     "tw-animate-css": "^1.4.0",
     "typescript": "~5.9.3",
     "typescript-eslint": "^8.48.0",
-    "vite": "^7.3.1"
+    "vite": "^7.3.1",
+    "vitest": "^4.0.18"
   }
 }