fix(frontend): exclude test types from production build config

Override the types array in tsconfig.build.json to prevent
vitest and testing-library type definitions from being required
during production builds. These are devDependencies only needed
for test compilation.

Fixes CI E2E workflow failure: TS2688 "Cannot find type definition file"

frontend/tsconfig.build.json

@@ -1,5 +1,9 @@
 {
   "extends": "./tsconfig.json",
+  "compilerOptions": {
+    // Override types to exclude test-only type definitions for production build
+    "types": []
+  },
   "exclude": [
     "src/**/*.test.ts",
     "src/**/*.test.tsx",