test: add comprehensive automated test coverage

- Vitest multi-project setup (unit / integration / component)
- Real-Postgres integration harness via in-process PGlite (TEST_DATABASE_URL
  override), migrations applied per worker; production code untouched
- Unit: routing, locale, validation/Zod schemas, metadata, mail, site-theme,
  marquee, media, portfolio helpers, plus architecture-rule tests
- Integration: Prisma data layer, API routes, and all server actions
- Component: UI primitives and form components (jsdom + Testing Library)
- 371 tests passing

package.json

@@ -43,12 +43,20 @@
     "zod": "^4.3.6"
   },
   "devDependencies": {
+    "@electric-sql/pglite": "^0.5.4",
+    "@electric-sql/pglite-socket": "^0.2.7",
+    "@testing-library/dom": "^10.4.1",
+    "@testing-library/jest-dom": "^7.0.0",
+    "@testing-library/react": "^16.3.2",
+    "@testing-library/user-event": "^14.6.3",
     "@types/node": "^20",
     "@types/pg": "^8.18.0",
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
     "eslint": "^9.39.4",
     "eslint-config-next": "^16.1.6",
+    "jsdom": "^30.0.1",
+    "pglite-prisma-adapter": "^0.7.2",
     "postcss": "^8",
     "prisma": "^7.4.2",
     "tailwindcss": "^3.4.1",