build(frontend): add Vitest setup and update Angular/TypeScript config

frontend/vitest.config.ts

@@ -1,10 +1,18 @@
 import { defineConfig } from 'vitest/config';
 
 export default defineConfig({
+  resolve: {
+    alias: {
+      // The package ships only a `module` field, which Vite's resolver
+      // can't always find — point it at the file directly.
+      '@plausible-analytics/tracker':
+        '@plausible-analytics/tracker/plausible.js',
+    },
+  },
   test: {
     globals: true,
     environment: 'jsdom',
-    include: ['src/**/*.vitest.ts', 'src/**/*.spec.vitest.ts'],
+    include: ['src/**/*.vitest.ts'],
     setupFiles: ['./vitest.setup.ts'],
     coverage: {
       provider: 'v8',