## What changed
Advertise `zstd-stream-v1` compression for WebSocket and Unix socket connections and use the negotiated codec for JSON-RPC messages. Retain compression history for the connection and keep plain-text messaging when compression is not negotiated.
Fragment compressed writes to respect the server's advertised frame limit, reject text messages in compressed sessions, and stop using the connection after a failed write to avoid mismatched compression history.
## Testing
Add an integration test covering compression negotiation, fragmentation, retained codec history, request/response handling, and disconnection on an uncompressed text message.
GitOrigin-RevId: 510073444ea49376a116c05214bcb79bd0bc3b50
