- Implement DM pairing flow for Discord and WhatsApp (checkDMPolicy, sendPairingReply with debounce)
- Add "pairing" case to BaseChannel.CheckPolicy() to reject instead of falling through to "open"
- Add group pending history tracking to Discord (record when not mentioned, prepend context when mentioned)
- Resolve Discord display names with priority: server nickname > global name > username
- Fix Gemini collapse format to prevent model from imitating tool call patterns
- Fix formatTokens crash on null/undefined input