Session chat archiving mechanism

[jeffwweee]

Problem

Session files in state/sessions/{chat_id}.md grow indefinitely as conversation history accumulates. This bloats context and reduces performance.

Proposal

Implement an archiving mechanism with configurable thresholds:

Options to explore

1. Time-based - Archive chats older than X days
2. File size-based - Archive when file exceeds X KB
3. File length-based - Archive when file exceeds X lines

Archive behavior

When threshold is reached:

• Move old messages to state/sessions/archive/{chat_id}-{timestamp}.md
• Keep recent N messages in active session file
• Optionally compress archived files

Acceptance criteria

• Archiving threshold configurable
• Old messages moved to archive (not deleted)
• Active session file stays manageable size
• Archive files stored in dedicated directory

Related

• Part of session management system
• Helps with context window management