Improve visibility into why images might not be analyzed in some channels.
Changes:
- Add permission check for 'Manage Messages' before processing
- Add debug logging when skipping messages (already analyzed, no media)
- Add info logging when checking messages (shows channel, attachments, embeds)
- Add warning when AI provider not configured
- Add channel name to rate limit warnings
Debug output now shows:
- Which channels lack permissions
- Why messages are skipped
- Rate limit status per channel
- AI provider configuration status
Helps diagnose: 'bot niet pakt in alle chats de content van images'