feat(FN-005): implement frontend foundation with auth and routing

- Add OIDC authentication with PKCE flow
- Create dashboard shell with sidebar and header
- Implement project management UI (list, create, detail)
- Add tool spawn page with tool/project selection
- Create tool instance detail page with status and controls
- Set up React Router with route guards
- Add Zustand auth store and API client with types

apps/web/src/pages/DashboardPage.tsx

@@ -0,0 +1,28 @@
+import { useAuthStore } from '../stores/auth'
+
+export default function DashboardPage() {
+  const { user } = useAuthStore()
+
+  return (
+    <div className="p-6">
+      <h1 className="text-3xl font-bold mb-4">Dashboard</h1>
+      <p className="text-lg mb-4">
+        Welcome back, {user?.display_name || user?.email || 'User'}!
+      </p>
+      <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4">
+        <div className="p-4 rounded-lg border border-border bg-surface">
+          <h2 className="text-xl font-semibold mb-2">Projects</h2>
+          <p className="text-gray-400">Manage your projects and repositories</p>
+        </div>
+        <div className="p-4 rounded-lg border border-border bg-surface">
+          <h2 className="text-xl font-semibold mb-2">Tools</h2>
+          <p className="text-gray-400">Spawn and manage development tools</p>
+        </div>
+        <div className="p-4 rounded-lg border border-border bg-surface">
+          <h2 className="text-xl font-semibold mb-2">Settings</h2>
+          <p className="text-gray-400">Configure your account and preferences</p>
+        </div>
+      </div>
+    </div>
+  )
+}