Adds /history [n] to display the last N user/assistant messages from
the current session (default 10, max 50).
- Tool and system messages are filtered out for readability
- Long messages are truncated to 200 characters with an ellipsis
- Multimodal content (image blocks) is collapsed to its text parts
- Invalid count argument returns a usage hint
- /history n uses prefix routing; /history uses exact routing
Also registers /history in build_help_text().
channel_id is already assigned from self._channel_key(message.channel)
earlier in the same function. The second identical assignment on line 453
is dead code left over from a copy-paste.
The /status command divided context_used by 1000 but context_total by
1024, producing inconsistent values. For example a 128000-token window
displayed as 125k instead of 128k. Tokens are not a binary unit, so
both should use 1000.
len(content) counts Unicode code points, not UTF-8 bytes. For non-ASCII
content such as Chinese or emoji, the reported count would be lower than
the actual bytes written to disk, which is misleading to the agent.