impl/p0-discussion-broadcast
main
- DISCUSSION_PROMPT_TEMPLATE 改为 Gitea API(Issue comment + sub Issue 创建) - _build_discussion_prompt 从 must_haves 解析 repo/issue_number 注入模板 - _broadcast_claim 判断 action_type=issue_discussion → 用 discussion prompt - 新增 _get_task_action_type 辅助方法 - Gitea 创建 flow/direct 和 flow/discuss label