feat: add unit tests (Rust parser+DB, Vitest frontend) and test workflow

package.json

@@ -7,7 +7,9 @@
     "dev": "vite",
     "build": "tsc && vite build",
     "preview": "vite preview",
-    "tauri": "tauri"
+    "tauri": "tauri",
+    "test": "vitest run",
+    "test:watch": "vitest"
   },
   "dependencies": {
     "@tanstack/react-query": "^5.99.2",
@@ -22,12 +24,18 @@
   "devDependencies": {
     "@tailwindcss/vite": "^4.2.4",
     "@tauri-apps/cli": "^2",
+    "@testing-library/jest-dom": "^6.0.0",
+    "@testing-library/react": "^16.0.0",
+    "@testing-library/user-event": "^14.0.0",
     "@types/react": "^19.1.8",
     "@types/react-dom": "^19.1.6",
     "@vitejs/plugin-react": "^6.0.1",
+    "@vitest/coverage-v8": "^3.0.0",
     "esbuild": "^0.28.0",
+    "jsdom": "^26.0.0",
     "tailwindcss": "^4.2.4",
     "typescript": "~5.8.3",
-    "vite": "^8.0.9"
+    "vite": "^8.0.9",
+    "vitest": "^3.0.0"
   }
 }