feat: expose health probes and metrics

app/api/metrics/route.ts

@@ -0,0 +1,5 @@
+import { timingSafeEqual } from "node:crypto";
+import { NextResponse } from "next/server";
+import { prometheusMetrics } from "@/lib/metrics";
+export const dynamic = "force-dynamic";
+export async function GET(request: Request) { const expected = process.env.METRICS_TOKEN; const supplied = request.headers.get("authorization")?.replace(/^Bearer\s+/i, "") || ""; if (expected) { const actual = Buffer.from(supplied), target = Buffer.from(expected); if (actual.length !== target.length || !timingSafeEqual(actual, target)) return NextResponse.json({ error: "Unauthorized" }, { status: 401 }); } return new NextResponse(prometheusMetrics(), { headers: { "Content-Type": "text/plain; version=0.0.4; charset=utf-8", "Cache-Control": "no-store" } }); }