Import Tripoli Cloud frontend prototype

React/TypeScript/Vite/Tailwind prototype from the design session (login,
dashboard, photos, backups, settings views with mocked API layer).
Infra work (Rust services, Ansible, OpenTofu) follows in subsequent commits.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/src/api/client.ts

@@ -0,0 +1,13 @@
+/**
+ * Every function in src/api/ is written as if it called `API_BASE`, but
+ * currently resolves a local mock after a short simulated delay. Swapping
+ * in a real backend later means rewriting the body of these functions only
+ * — components and hooks never change.
+ */
+export const API_BASE = import.meta.env.VITE_API_URL;
+
+export function mockFetch<T>(data: T, delayMs = 220): Promise<T> {
+  return new Promise((resolve) => {
+    setTimeout(() => resolve(data), delayMs);
+  });
+}