/btw command leaks context from before /clear

Summary

The /btw slash command retains conversation context from a previous session even after /clear has been run, causing it to answer based on stale information.

Steps to reproduce

1. Start a session, have some conversation (e.g. checking git branch/status)
2. Run /clear to reset the conversation
3. Run /btw <question> — it answers as if /clear never happened

Expected behaviour

/btw should answer based only on the current (post-clear) conversation context.

Actual behaviour

/btw leaks context from the cleared session. In the observed case, it described the wrong git branch (from the pre-clear session) when asked about the last interaction.

Environment

• Platform: macOS (Darwin 25.5.0)
• Shell: zsh