- Consolidate extractImageKey/extractFileKey/extractFileName into shared
extractJSONStringField helper to reduce code duplication
- Move mentionPlaceholderRegex to package-level position after imports
- Rename feishuCfg field to config for clarity within FeishuChannel
- Replace @_user_1 heuristic with GET /open-apis/bot/v3/info API call
at startup for reliable bot @mention detection
- Fix double close on file handle in downloadResource by removing defer
and using explicit close in both success and error paths
- Add unit tests for common.go and feishu_64.go helpers (53 test cases)
Upgrade the Feishu channel from basic text-only to full feature parity with
Telegram/Discord: interactive card messages with markdown rendering, message
editing (MessageEditor), placeholder messages (PlaceholderCapable), emoji
reactions (ReactionCapable), and inbound/outbound media support (MediaSender).
Also add @mention detection with lazy bot open_id discovery, group trigger
filtering with mention awareness, and multi-type inbound message parsing
(text, post, image, file, audio, video).
Hoshina