🐛 fix: restore plugin auth and proxy connection info

apps/backend/src/middleware/api-key.ts

@@ -0,0 +1,19 @@
+import { prisma } from "@minikura/db";
+
+export async function findApiKeyOwner(apiKey: string) {
+  if (!apiKey) return null;
+
+  const [server, proxy] = await Promise.all([
+    prisma.server.findUnique({ where: { api_key: apiKey }, select: { id: true } }),
+    prisma.reverseProxyServer.findUnique({ where: { api_key: apiKey }, select: { id: true } }),
+  ]);
+
+  if (server) return { kind: "server" as const, id: server.id };
+  if (proxy) return { kind: "reverse-proxy" as const, id: proxy.id };
+  return null;
+}
+
+export function bearerToken(header: string | null): string {
+  if (!header?.startsWith("Bearer ")) return "";
+  return header.slice(7).trim();
+}