Non-EVM chain outbound performance improvement with batch keysign

[ws4charlie]

Describe the Issue

There are still potentials to improve outbound performance for non-EVM chains.

1. Solana outbound might benefit from batch keysign strategy like EVM chains.
2. Bitcoin outbound may or may not benefit from batch keysign strategy, need to investigate.
3. TON needs to investigate if batch keysign can be used or not.
4. Sui outbound can't benefit from batch keysign, because pre-signed transactions can be easily invalidated due to the constantly changing gateway object's version.