Initial commit: StackPilot Phase 1 (Core)

Self-hosted Docker Compose manager.
- Backend: FastAPI + docker-py + SQLite (JWT auth, file-first stacks,
  lifecycle, live status, WebSocket logs, docker-run converter, audit log)
- Frontend: React + Vite + Tailwind (login/setup, dashboard, stacks,
  stack detail, Monaco editor, dark/light theme)
- Deployment: docker-compose.yml, Dockerfiles, nginx reverse proxy

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/components/layout/Topbar.tsx

@@ -0,0 +1,22 @@
+import { useLocation } from "react-router-dom";
+
+const titles: Record<string, string> = {
+  "": "Dashboard",
+  stacks: "Stacks",
+  networks: "Networks",
+  images: "Images",
+  templates: "Templates",
+  settings: "Settings",
+};
+
+export function Topbar() {
+  const { pathname } = useLocation();
+  const segment = pathname.split("/")[1] ?? "";
+  const title = titles[segment] ?? "StackPilot";
+
+  return (
+    <header className="flex h-14 items-center justify-between border-b border-slate-200 bg-card px-6 dark:border-slate-700 dark:bg-card-dark">
+      <h1 className="text-base font-semibold">{title}</h1>
+    </header>
+  );
+}