admin(machines): add resilient fallback for details page

- Keep Convex useQuery for machines.getById
- Add HTTP fallback via /api/admin/machines/[id]/details if query stays loading (>1.2s)
- Helps when websocket/convex-react doesn’t initialize and avoids permanent skeleton

src/app/api/admin/machines/[id]/details/route.ts

@@ -0,0 +1,23 @@
+import { NextResponse } from "next/server"
+import type { Id } from "@/convex/_generated/dataModel"
+import { api } from "@/convex/_generated/api"
+import { createConvexClient, ConvexConfigurationError } from "@/server/convex-client"
+
+export const dynamic = "force-dynamic"
+
+export async function GET(_req: Request, { params }: { params: { id: string } }) {
+  try {
+    const client = createConvexClient()
+    const id = params.id as Id<"machines">
+    const data = (await client.query(api.machines.getById, { id, includeMetadata: true })) as unknown
+    if (!data) return NextResponse.json({ error: "Not found" }, { status: 404 })
+    return NextResponse.json(data, { status: 200 })
+  } catch (err) {
+    if (err instanceof ConvexConfigurationError) {
+      return NextResponse.json({ error: err.message }, { status: 500 })
+    }
+    console.error("[api] admin/machines/[id]/details error", err)
+    return NextResponse.json({ error: "Internal error" }, { status: 500 })
+  }
+}
+