feat: add deployment reload controls

app/api/active/route.ts

@@ -0,0 +1,28 @@
+import { readFile } from "node:fs/promises";
+import path from "node:path";
+import { sse } from "@/lib/realtime/sse";
+
+export const dynamic = "force-dynamic";
+
+async function getDeploymentVersion() {
+  if (process.env.NODE_ENV === "development") return "DEV";
+
+  try {
+    const version = await readFile(path.join(process.cwd(), ".version"), "utf8");
+    return version.trim() || null;
+  } catch {
+    return null;
+  }
+}
+
+export async function GET(request: Request) {
+  const version = await getDeploymentVersion();
+  if (!version) {
+    return new Response("Deployment version unavailable", { status: 503 });
+  }
+
+  return sse.active.stream({
+    signal: request.signal,
+    motd: { event: "version", data: version },
+  });
+}