Support resumable game folder uploads and remove DLC declarations

src/lib/server/game-files/http.ts

@@ -7,7 +7,8 @@ import { assertRegularPath, parseByteRange } from './storage.js';
 
 export function gameFileError(cause: unknown): Response {
     const status = typeof cause === 'object' && cause !== null && 'status' in cause && typeof cause.status === 'number' ? cause.status : 400;
-    return json({ error: cause instanceof Error ? cause.message : 'Game file request failed.' }, { status });
+    const receivedBytes = typeof cause === 'object' && cause !== null && 'receivedBytes' in cause && Number.isSafeInteger(cause.receivedBytes) ? cause.receivedBytes : undefined;
+    return json({ error: cause instanceof Error ? cause.message : 'Game file request failed.', ...(receivedBytes === undefined ? {} : { receivedBytes }) }, { status });
 }
 export async function readGameJson(request: Request, maxBytes = 64 * 1024): Promise<Record<string, unknown>> {
     if (!request.body) throw new Error('A JSON request body is required.');