Robot meeting participation: join/leave active meetings by 9-digit number and stream real-time events.

• Three core commands: +meeting-join to join a meeting (creates real attendance record), +meeting-events to read live participant/chat/screen-share events, and +meeting-leave to exit
• Bot must actually join a meeting before reading its event stream; event visibility is limited to in-progress meetings where the bot is an active participant
• Requires meeting.id (long numeric ID returned by join) for event queries and leaving, not the 9-digit meeting number
• Default to --page-all for event queries and always check for pagination signals (has_more=true, page_token) to avoid incomplete results
• Complements lark-vc skill (post-meeting queries like notes/transcripts/participant snapshots) and integrates with lark-im for downstream message distribution