add timesheet unit and e2e tests; add unit test CI setup

vitest.config.ts

@@ -0,0 +1,19 @@
+import { defineConfig } from 'vitest/config';
+import vue from '@vitejs/plugin-vue';
+import { fileURLToPath } from 'node:url';
+
+export default defineConfig({
+    plugins: [vue()],
+    resolve: {
+        alias: {
+            '@': fileURLToPath(new URL('./resources/js', import.meta.url)),
+        },
+    },
+    test: {
+        environment: 'happy-dom',
+        globals: false,
+        setupFiles: ['./resources/js/test-setup.ts'],
+        include: ['resources/js/**/*.{test,spec}.{ts,tsx}'],
+        exclude: ['**/node_modules/**', '**/e2e/**', '**/dist/**'],
+    },
+});