skills(pm-dispatch): dedupe at grading by file/mechanism over the open board of both repos before keywords; same finding ⇒ duplicate_of, never a second dispatch

The triage band's shadow rows (:366–:368) read as a cross-repo keyword search
only. Two cards on one file and one defect were graded two days apart into
two lanes by the same seat, both dispatched, and the second PR closed as
superseded — the step that was missing is dedupe by FILE / MECHANISM against
the OPEN board (own repo and sibling repos, `pm:dispatched` included) before
keywords, with the finding — not the card — as the unit: the later card's
evidence moves to the earlier card and the later card closes `duplicate_of`.

Paid in-band at 812 / 812: the three rows are rewritten, no line added, no
re-wrap; every retired clause survives in the same band (see the PR body).

Claude-Session: https://claude.ai/code/session_01BTeBejoPUvRHN8WdAJC6oF
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude

.claude/skills/pm-dispatch/SKILL.md

@@ -363,9 +363,9 @@ PM 的工作是循环:选卡 → 认领 → 派发 → 收集 → 复核 → 报
 - 父单已有子结构的:父单队列标签即可,分诊逐个展开路由、补 `Blocked-by:` 排序。
 - 父单是协调节点,永不派发。
 - 每张留一条英文审计评论(`Triage: lands in …; rationale: …`),可选带 `Size/model suggestion:` 行。
-- 跨仓查重(shadow 检查):跟跨仓引用 + 关键词搜各姊妹仓。
-- shadow 命中在飞 ⇒ `Blocked-by:` 不派;open 未认领 ⇒ 先收敛成一个派发入口。
-- shadow 命中已完成 ⇒ 卡可能过期。
+- 查重/shadow 检查先按文件/机制查本仓与姊妹仓 open 卡(含 `pm:dispatched`),再跟引用与关键词。
+- 同文件同缺陷 = 同一发现,不分车道:证据搬到先卡,后卡关 `duplicate_of`,⛔ 不并排派发。
+- 其余在飞 ⇒ `Blocked-by:` 不派;open 未认领 ⇒ 先并成一个派发入口;已完成 ⇒ 卡可能过期。
 - 生产者在哪是常设分诊问题:declared ≠ enforced 形状的卡先问谁在写这个字段。
 - 派发前按生产者的答案改卡的范围与域标签。
 - 发现分诊轮:`finding` 恒 = 待首次定级、定级即离标;hold 重验只在 `Restart-when:` 命中时发生。