* feat(config): add Lark/Feishu channel config support
- Add LarkConfig struct with app_id, app_secret, encrypt_key, verification_token, allowed_users, use_feishu fields
- Add lark field to ChannelsConfig
- Export LarkConfig in config/mod.rs
- Add 5 tests for LarkConfig serialization/deserialization
Related to #164
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* fix: apply cargo fmt formatting
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
