Add ds max chann entry config

[zjg555543]

issue

• In the XLayer testnet, when synchronizing blocks from 0, the following error occurs: the data stream relay sends too fast, but the client cannot process it in time, causing the relay to forcibly terminate the TCP connection.

[INFO] [12-26|07:15:37.066] Starting L1 syncer thread 
[INFO] [12-26|07:15:37.792] [2/16 L1InfoTree] Info tree updates      count=2 latestIndex=151882
[INFO] [12-26|07:15:37.793] [2/16 L1InfoTree] Finished L1 Info Tree stage 
[INFO] [12-26|07:15:37.793] [3/16 Batches] Starting batches stage 
[INFO] [12-26|07:15:37.793] [Datastream client] Starting datastream client from cold 
[INFO] [12-26|07:15:38.347] [3/16 Batches] Highest block in datastream datastreamBlock=20616385 stageProgressBlockNo=12788219
[INFO] [12-26|07:15:38.347] [3/16 Batches] Reading blocks from the datastream. 
[INFO] [12-26|07:15:38.348] [3/16 Batches] Started downloading L2Blocks routine ID: 748875 
[INFO] [12-26|07:15:48.347] [3/16 Batches] Downloaded blocks from datastream progress: 12459 
[INFO] [12-26|07:15:58.347] [3/16 Batches] Downloaded blocks from datastream progress: 13265 
[INFO] [12-26|07:16:08.348] [3/16 Batches] Downloaded blocks from datastream progress: 13992 
[WARN] [12-26|07:16:11.514] Error in datastream client, stopping consumption 
[INFO] [12-26|07:16:11.514] [3/16 Batches] Total blocks written: 14873 
[INFO] [12-26|07:16:11.514] [3/16 Batches] Saving stage progress     lastBlockHeight=12803092
[INFO] [12-26|07:16:11.514] [3/16 Batches] Finished writing blocks   blocksWritten=14873 elapsed=33.721673063s
[INFO] [12-26|07:16:11.514] [3/16 Batches] Finished Batches stage 
[WARN] [12-26|07:16:11.514] [3/16 Batches] Error downloading blocks from datastream error="readAllFullL2BlocksToChannel: NextFileEntry: reading file data bytes: readBuffer: socket error: io.ReadFull: unexpected EOF"
[INFO] [12-26|07:16:11.514] [3/16 Batches] Ended downloading L2Blocks routine ID: 748875 

approach

• This PR attempts to increase the channel buffer and exit the synchronization logic only after the buffer is processed.

[afa7789]

legit.

with a flag.