refactor(web): set up component test infra + decompose ProjectWizard

Phase 4a: Add @testing-library/react, user-event, jest-dom, jsdom.
Switch vitest environment to jsdom, add setup file, create test-utils
with QueryClient wrapper.

Phase 4b: Extract ProjectWizard form logic into project-wizard/ subdir:
- types.ts: WizardState, Assignment, constants, factory functions
- useProjectWizardForm.ts: form state hook + canGoNext pure function

Phase 4c: 32 tests for canGoNext validation (all 5 steps), makeDefaultState,
and makeReq factory function.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/test-utils.tsx

@@ -0,0 +1,24 @@
+import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
+import { render, type RenderOptions } from "@testing-library/react";
+import type { ReactElement } from "react";
+
+function createTestQueryClient() {
+  return new QueryClient({
+    defaultOptions: {
+      queries: { retry: false, gcTime: 0 },
+      mutations: { retry: false },
+    },
+  });
+}
+
+function TestProviders({ children }: { children: React.ReactNode }) {
+  const queryClient = createTestQueryClient();
+  return <QueryClientProvider client={queryClient}>{children}</QueryClientProvider>;
+}
+
+function customRender(ui: ReactElement, options?: Omit<RenderOptions, "wrapper">) {
+  return render(ui, { wrapper: TestProviders, ...options });
+}
+
+export * from "@testing-library/react";
+export { customRender as render };