ui(deploy): scaffold AppDeploymentPage + route /apps/new and /apps/:slug

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

ui/src/pages/AppsTab/AppDeploymentPage/index.tsx

@@ -0,0 +1,26 @@
+import { useParams, useLocation } from 'react-router';
+import { useEnvironmentStore } from '../../../api/environment-store';
+import { useEnvironments } from '../../../api/queries/admin/environments';
+import { useApps } from '../../../api/queries/admin/apps';
+import { PageLoader } from '../../../components/PageLoader';
+import styles from './AppDeploymentPage.module.css';
+
+export default function AppDeploymentPage() {
+  const { appId } = useParams<{ appId?: string }>();
+  const location = useLocation();
+  const selectedEnv = useEnvironmentStore((s) => s.environment);
+  const { data: environments = [], isLoading: envLoading } = useEnvironments();
+  const { data: apps = [], isLoading: appsLoading } = useApps(selectedEnv);
+
+  const isNetNew = location.pathname.endsWith('/apps/new');
+  const app = isNetNew ? null : apps.find((a) => a.slug === appId) ?? null;
+
+  if (envLoading || appsLoading) return <PageLoader />;
+
+  return (
+    <div className={styles.container}>
+      <h2>{app ? app.displayName : 'Create Application'}</h2>
+      {/* Identity section, tabs, primary button land in subsequent tasks */}
+    </div>
+  );
+}