## What changed
- Configure the code-mode host to send zstd-compressed responses when clients advertise support, and enable both client transports to accept them.
- Preserve uncompressed responses for clients that do not advertise zstd support.
- Patch `tonic` in Bazel builds to use zstd compression level 1, favoring response latency over compression ratio.
## Testing
Extend the TCP session integration test to check response encoding and successful session opening for both zstd-capable and uncompressed-only clients.
GitOrigin-RevId: b6cf0da51dd30fc2ac9a1b0af11bec26555c559d