Add im +chat-list shortcut wrapping GET /open-apis/im/v1/chats (previously not exposed via lark-cli).
Add --exclude-muted to both +chat-search and +chat-list: client-side filter that calls POST /open-apis/im/v1/chat_user_setting/batch_get_mute_status after each page and drops is_muted=true chats.
Introduce shortcuts/im/mute_filter.go with pure helpers and an orchestrator (MaybeApplyMuteFilter) shared by both shortcuts.
Change-Id: I22221ac5835667f58cbd40b34de75825d2445d1c