Add Feishu Channel

This skill adds Feishu (飞书/Lark) support to NanoClaw using the skills engine for deterministic code changes, then walks through interactive setup.

Phase 1: Pre-flight

Check if already applied

Read .nanoclaw/state.yaml. If feishu is in applied_skills, skip to Phase 3 (Setup). The code changes are already in place.

Ask the user

Use AskUserQuestion to collect configuration:

AskUserQuestion: Do you have a Feishu (Lark) app already created, or do you need to create one?

If they have one, ask for the App ID and App Secret. If not, walk them through creation in Phase 3.

Phase 2: Apply Code Changes