feat(feishu): add Feishu inbound webhook, /gh commands and card actions

- add feishu_links D1 table and link store helpers
- implement X-Lark-Signature verification, url_verification, /gh login|logout|comment|merge|close and card.action.trigger Merge/Close
- render interactive cards with clickable title link, inline links and callback buttons (no whole-card card_link)
- bind Feishu account in OAuth callback
- document event subscription and required scopes

docs/zh/guide/logs.md

@@ -11,7 +11,7 @@
 | `event`      | 事件类型（如 `push`、`pull_request`、`custom`）          |
 | `repo`       | 仓库全名（存在时）                                       |
 | `target`     | 消息发送到的目标 id                                      |
-| `platform`   | `discord` 或 `telegram`                                  |
+| `platform`   | `discord`、`telegram` 或 `feishu`                       |
 | `ok`         | 发送是否成功                                             |
 | `status`     | 平台 API 的 HTTP 状态码（适用时）                        |
 | `error`      | 失败时的错误信息                                         |