add unit tests

this adds the groundwork to start unit testing some modules

src/package.json

@@ -17,7 +17,8 @@
     "check:all": "pnpm typecheck && pnpm lint && pnpm format:check && pnpm build",
     "db:generate": "drizzle-kit generate",
     "cli:build": "node cli/build.js",
-    "cli:dev": "tsx cli/index.ts"
+    "cli:dev": "tsx cli/index.ts",
+    "test:unit": "vitest run --project unit"
   },
   "dependencies": {
     "@eschricht/nuxt-color-mode": "^1.2.0",
@@ -56,9 +57,12 @@
   },
   "devDependencies": {
     "@nuxt/eslint": "^1.14.0",
+    "@nuxt/test-utils": "^3.23.0",
     "@types/debug": "^4.1.12",
     "@types/phc__format": "^1.0.1",
     "@types/semver": "^7.7.1",
+    "@vitest/coverage-v8": "^4.0.18",
+    "@vitest/ui": "4.0.18",
     "drizzle-kit": "^0.31.8",
     "esbuild": "^0.27.3",
     "eslint": "^9.39.2",
@@ -67,6 +71,7 @@
     "prettier-plugin-tailwindcss": "^0.7.2",
     "tsx": "^4.21.0",
     "typescript": "^5.9.3",
+    "vitest": "^4.0.18",
     "vue-tsc": "^3.2.4"
   },
   "packageManager": "pnpm@10.29.2"