Minecraft 26.2 Fabric server stack with CraftDeck management panel

- docker-compose: itzg/minecraft-server (Fabric, offline mode, whitelist
  enforced, Modrinth-managed mods), itzg/mc-backup sidecar, custom dashboard
- Gated auth for offline mode: approve username -> whitelisted with a short
  registration window -> EasyAuth /register + /login; auto-revoke on expiry
- CraftDeck panel (Next.js 16, zero native deps): live console (SSE), players
  & stats, lag diagnostics (server TPS vs player ping via spark), performance
  graphs, Modrinth mod search/manager, backups & restore, sandboxed file
  browser/editor, .env config editor with compose apply, cron schedules,
  Discord alerts, scrypt-hashed panel login
- scripts/setup.sh generates secrets; docs/ covers auth, mods, updating,
  backups, networking (Tailscale), troubleshooting

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

dashboard/src/app/api/files/upload/route.ts

@@ -0,0 +1,21 @@
+import { NextRequest } from "next/server";
+import path from "node:path";
+import { writeBinaryFile } from "@/server/files";
+import { ok, fail, handle } from "@/server/api";
+
+const MAX_UPLOAD = 256 * 1024 * 1024; // mod jars and datapacks, not world dumps
+
+export async function POST(req: NextRequest) {
+  return handle(async () => {
+    const form = await req.formData();
+    const dir = (form.get("dir") as string) ?? "";
+    const file = form.get("file");
+    if (!(file instanceof File)) return fail("Missing file");
+    if (file.size > MAX_UPLOAD) return fail("File too large (256 MB max)");
+    const name = path.basename(file.name);
+    if (!name || name.startsWith(".")) return fail("Invalid file name");
+    const buf = Buffer.from(await file.arrayBuffer());
+    writeBinaryFile(path.join(dir, name), buf);
+    return ok({ uploaded: name, size: file.size });
+  });
+}