chore: import upstream snapshot with attribution

apps/webapp/app/routes/healthcheck.tsx

@@ -0,0 +1,27 @@
+import { prisma } from "~/db.server";
+import type { LoaderFunction } from "@remix-run/node";
+import { env } from "~/env.server";
+import { rbac } from "~/services/rbac.server";
+
+export const loader: LoaderFunction = async ({ request }) => {
+  try {
+    // Resolve the lazy plugin controller so plugin-load failures surface
+    // during readiness probes. With REQUIRE_PLUGINS=1, a failed plugin
+    // load throws here and the rollout's readiness probe fails. The
+    // fallback path doesn't touch the DB, so this runs even when
+    // HEALTHCHECK_DATABASE_DISABLED=1 — REQUIRE_PLUGINS protection must
+    // not be silently bypassed by the DB-disabled flag.
+    await rbac.isUsingPlugin();
+
+    if (env.HEALTHCHECK_DATABASE_DISABLED === "1") {
+      return new Response("OK");
+    }
+
+    await prisma.$queryRaw`SELECT 1`;
+
+    return new Response("OK");
+  } catch (error: unknown) {
+    console.log("healthcheck ❌", { error });
+    return new Response("ERROR", { status: 500 });
+  }
+};