refactor(swipe): split swipe screen modules

Move swipe screen logic into hooks/services and extract
state-specific UI components to keep files small while
preserving existing behavior.

Reference: US-002

.codex/skills/dev-browser/scripts/start-relay.ts

@@ -0,0 +1,32 @@
+/**
+ * Start the CDP relay server for Chrome extension mode
+ *
+ * Usage: npm run start-extension
+ */
+
+import { serveRelay } from "@/relay.js";
+
+const PORT = parseInt(process.env.PORT || "9222", 10);
+const HOST = process.env.HOST || "127.0.0.1";
+
+async function main() {
+  const server = await serveRelay({
+    port: PORT,
+    host: HOST,
+  });
+
+  // Handle shutdown
+  const shutdown = async () => {
+    console.log("\nShutting down relay server...");
+    await server.stop();
+    process.exit(0);
+  };
+
+  process.on("SIGINT", shutdown);
+  process.on("SIGTERM", shutdown);
+}
+
+main().catch((err) => {
+  console.error("Failed to start relay server:", err);
+  process.exit(1);
+});