test: add @vitest/coverage-v8 + test:coverage to all workspaces

apps/admin/package.json

@@ -9,7 +9,8 @@
     "preview": "vite preview",
     "typecheck": "tsc -b",
     "test": "vitest run",
-    "test:watch": "vitest"
+    "test:watch": "vitest",
+    "test:coverage": "vitest run --coverage"
   },
   "dependencies": {
     "@solelog/shared": "workspace:*",
@@ -26,6 +27,7 @@
     "@types/react": "^18.3.0",
     "@types/react-dom": "^18.3.0",
     "@vitejs/plugin-react": "^4.3.0",
+    "@vitest/coverage-v8": "^3",
     "jsdom": "^25.0.0",
     "typescript": "^5.7.2",
     "vite": "^7.0.0",