feat(feishu): add require_mention and free_response_chats config for group messages

[batmanhz]

Summary

Align Feishu platform with other messaging platforms (Telegram, Discord, WhatsApp) by introducing a configurable mention requirement for group messages.

Changes

1. New Configuration Options

• require_mention (default: true): Controls whether group messages must @mention the bot to trigger processing.
• free_response_chats (default: []): Whitelist of specific group chat IDs that bypass both mention and user allowlist checks.

2. Configuration Support

• YAML config: feishu.require_mention, feishu.free_response_chats
• Environment variables: FEISHU_REQUIRE_MENTION, FEISHU_FREE_RESPONSE_CHATS

3. Files Modified

• gateway/platforms/feishu.py: Added settings, parsing, and updated _should_accept_group_message logic.
• gateway/config.py: Added free_response_chats to the platform config bridge.
• hermes_cli/config.py: Added new env vars to known keys.
• tests/gateway/test_feishu.py: Updated and added tests for the new behavior.

4. Usage Example

# config.yaml
feishu:
  require_mention: true  # Other groups still require @mention
  free_response_chats:
  - oc_6c6f73affa82ede1696fb7d8bcda4f1a  # This group bypasses all checks

5. Testing

All 189 Feishu tests pass locally.

[teknium1]

Thanks for the Feishu group-routing contribution. This is an automated hermes-sweeper review; current main already provides the requested behavior through the maintained Feishu admission policy.

• plugins/platforms/feishu/adapter.py:1600 resolves global require_mention from platform config or FEISHU_REQUIRE_MENTION; :4274 applies it in the live group-admission path.
• plugins/platforms/feishu/adapter.py:421 and :4278 provide per-chat group_rules.<chat_id>.require_mention overrides. A rule with policy: open and require_mention: false is the maintained equivalent of a free-response chat: it admits that chat without requiring a mention or the default user allowlist.
• The documented oc_free_chat example is at website/docs/user-guide/messaging/feishu.md:514, and coverage exists in tests/gateway/test_feishu_bot_admission.py:100 and :114.
• This fuller implementation landed in b94cb8e2c4e (feat(feishu): operator-configurable bot admission and mention policy) and shipped in v2026.5.7. The linked issue Feishu group messages ignore require_group_mention=false from config.yaml #15226 was also closed as resolved on current main.