feat(pr): 新增 slugify.sh 分支命名工具並修正 pr 技能稽核項目

What: 新增 tools/slugify.sh 腳本，將分支類型與短語轉成 ASCII slug；修改 skills/pr/SKILL.md，把原本內嵌在文字說明中的 slugify 規則改為呼叫 tools/slugify.sh，並把 Rules 段落中「分支標題摘要」與「描述撰寫」都標記為必須交由 sub agent 執行（原本只有描述撰寫一項），同時把一個非英文範例字串替換成全英文範例；plugin.json、.claude-plugin/plugin.json、.codex-plugin/plugin.json 三份 manifest 版本號由 0.0.1 升到 0.0.2。
Why: 因應 jsc-meta:skill-check 稽核結果，pr 技能有兩項不合規：決定性的分支名稱 slugify 流程應該工具化而非寫成文字規則，避免各 agent 各自理解出現落差；另外，需要判斷力的步驟（分支標題摘要、描述撰寫）標記不一致，只標了描述撰寫一項會讓分支標題摘要漏掉必要的 sub agent 隔離；範例字串混雜非英文也不符合技能文件全英文的要求。
How: 新增可執行的 tools/slugify.sh（小寫化、非 a-z0-9 字元轉連字號、合併連續連字號、去除頭尾連字號），並在 SKILL.md 步驟 3.2 改為呼叫此腳本；同步更新 Rules 第 3 項，把「分支標題摘要」與「描述撰寫」都列為必須交由 sub agent 執行；把範例改成全英文；三份 plugin manifest 版本號同步升版以反映此次修改。
Who: 影響 jsc-git 的 pr 技能與其新增的 slugify.sh 工具，屬 pr 流程分支命名與稽核合規的功能性變更。

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

skills/pr/SKILL.md

@@ -12,7 +12,7 @@ description: Commit all changes via jsc-git:commit, create a target branch named
 3. Create the target branch from the remote base branch:
    1. Take the type with the highest priority across all commits: `revert > fix > feat > perf > refactor > test > docs > style > chore`.
    2. Summarize one title from all commit messages.
-   3. Branch names allow **ASCII only**; always slugify as `{type}/{requirement or feature}-{title}`. Translate the requirement and title into a short English phrase first, then lowercase, replace every character outside `a-z0-9` with a hyphen, collapse consecutive hyphens, and trim leading and trailing hyphens (example: `feat/order-匯出報表` → `feat/order-export-report`). No spaces, parentheses, colons, or any non-ASCII character.
+   3. Branch names allow **ASCII only**; always slugify as `{type}/{requirement or feature}-{title}`. Translate the requirement and title into a short English phrase first, then call `tools/slugify.sh {type} {phrase}` to produce the final slug (example: translate a non-English request to English first, then slugify — "export report" → export-report → feat/order-export-report). No spaces, parentheses, colons, or any non-ASCII character.
 4. Run `git push -u origin {target branch}`.
 5. Create the PR: `jsc-gitea/tools/gitea.sh pr-create {owner}/{repo} {target branch} {base branch} "{branch name}" {description file}`.
    - Title = branch name.
@@ -26,4 +26,4 @@ description: Commit all changes via jsc-git:commit, create a target branch named
 
 1. No template section may stay empty: fill the literal 「無」 when there is no plan page, analyze page, or prerequisite PR.
 2. Take the plan page and analyze page links from the `jsc-sdlc` wiki pages; the analyze link must point at the work package heading anchor.
-3. The description drafting details **MUST run as a sub agent**.
+3. Branch title summarization (step 3.2) and description drafting MUST run as a sub agent.