Restore codebase deleted by bad auto-commit e4227cf

Commit e4227cf (a story creation auto-commit) erroneously deleted 175
files from master's tree, likely due to a race condition between
concurrent git operations. This commit re-adds all files from the
working directory.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/vitest.config.ts

@@ -0,0 +1,27 @@
+import react from "@vitejs/plugin-react";
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  plugins: [react()],
+  define: {
+    __BUILD_TIME__: JSON.stringify("2026-01-01T00:00:00.000Z"),
+  },
+  test: {
+    environment: "jsdom",
+    environmentOptions: {
+      jsdom: {
+        url: "http://localhost:3000",
+      },
+    },
+    globals: true,
+    testTimeout: 10_000,
+    setupFiles: ["./src/setupTests.ts"],
+    css: true,
+    exclude: ["tests/e2e/**", "node_modules/**"],
+    coverage: {
+      provider: "v8",
+      reporter: ["text", "json-summary"],
+      reportsDirectory: "./coverage",
+    },
+  },
+});