fix: remove leaked .claude cache, fix Hyperliquid duplicate subscription (#3)

- Remove .claude/tsc-cache (leaked local paths: /home/bokiko/Projects/...)
- Add .claude/ and .kyzn/.improve.lock to .gitignore
- Fix Hyperliquid: initial subscribe sent allMids (wrong), then re-subscribed
  to trades in onopen handler (duplicate). Now subscribes to trades directly
  in config and removes the redundant onopen special case.

Co-authored-by: bloxi <bloxi@butler.khalifa.network>

Author: bloxi-bot