feishu-topic-spawn

# Feishu Topic Spawn

Create a new Feishu topic in a dedicated **topic-group**, then optionally post the **first thread reply** inside it.

Keep this skill lightweight. Use it for topic creation and first-reply bootstrapping, not for session routing magic.

## Validated behavior

This workflow has been verified:

1. `feishu_im_user_message.send` to a topic-group `chat_id` creates a **new top-level topic**.
2. `feishu_im_user_message.reply` with `reply_in_thread=true` posts **inside that topic**.
3. A reply can `@` a user by placing Feishu text markup directly in the content:

```text
<at user_id="ou_xxx">Name</at> 你好
```

This is the current working path. Prefer it over assumptions about implicit reply routing.

## Preconditions

Require all of the following:

- The destination is a real **Feishu topic-group**.
- The user has explicitly asked to send the message.
- The user has permission to post in that group.
- User-auth Feishu messaging is available for `feishu_im_user_message`.

If user auth is unavailable or expired, stop and ask the user to re-authorize.

If the target group is not a topic-group, explain that the result will only be a normal group message, not a topic.

## Default target group

Default to the fixed topic-group configured in `TOOLS.md`.

Current default:
- `泡菜的话题群`

Use `feishu_chat` with `action=search` to resolve the group.

If no matching group is found:
- Stop.
- Tell the user the topic-group does not exist yet.
- Ask them to create it manually first.

## Workflow

### 1. Resolve target group

- If the user explicitly names a group, use that name.
- Otherwise default to `泡菜的话题群`.
- Resolve the `chat_id` with `feishu_chat.search`.

### 2. Parse requested action

Support four shapes:

#### A. Open topic only
Example:
```text
开话题：OpenClaw 多线程 SOP
```

Send one top-level text message only.

#### B. Open topic + first thread reply
Example:
```text
开话题：OpenClaw 多线程 SOP｜先写一个 5 点大纲
```

Interpret as:
- title = `O...