fix(git): 補齊稽核缺失並修掉護欄失效

What：依 jsc-meta:skill-check 的稽核結果修正技能與工具——補上每個步驟的可檢核完成條件、
把留在內文的標準輸入輸出流程下放 tools/、修正查表與退碼路由造成的誤判。

Why：稽核發現這些缺失會讓技能在實際執行時走錯分支或靜默通過。
完成條件缺漏是最常被違反的一項；退碼誤判與查表錯誤則會讓良性狀況被當成失敗。

How：逐項對照 references/guidelines.md 的審核檢查清單修正，新增的工具都有
documented exit codes，並以真實執行驗證每條路徑。

Who：jsc-meta:skill-check 例行稽核（2026-08-25）。

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

skills/pr/SKILL.md

@@ -7,23 +7,25 @@ description: Commit all changes via jsc-git:commit, create a target branch named
 
 ## Steps
 
-1. Call `jsc-git:commit` to commit every file change first.
-2. Pick the base branch. **A base branch passed in by the caller wins over everything else** — `jsc-sdlc:implement` passes the analysis page's source branch, and silently retargeting that PR at `develop` would merge a single work package straight past the feature branch it belongs to. Only when no caller supplied one: use `develop` when it exists on the remote, else `main`, else `master`. Verify the chosen base exists on the remote (`git fetch --prune origin` first, then `git branch -r`); it does not exist → report and stop, never fall back silently.
+1. Call `jsc-git:commit` to commit every file change first. Done when `git status --porcelain` prints nothing.
+2. Resolve the base branch: `tools/base-branch.sh {base branch the caller passed in, omitted when the caller passed none}`. **A base branch passed in by the caller wins over everything else** — `jsc-sdlc:implement` passes the analysis page's source branch, and silently retargeting that PR at `develop` would merge a single work package straight past the feature branch it belongs to. Done when the script prints one branch name; a non-zero exit → report and stop, never fall back silently.
 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 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}`.
+   1. Take the type with the highest priority across all commits: `revert > fix > feat > perf > refactor > test > docs > style > chore`. Done when exactly one type is picked.
+   2. Summarize one title from all commit messages. Done when one title line covers every commit in the range.
+   3. Translate the requirement and the title into a short English phrase, then run `tools/slugify.sh {type} {phrase}` to build the target branch name `{type}/{requirement or feature}-{title}` (example: a non-English request to export order reports becomes the phrase `order export report`, then `feat/order-export-report`). Done when the script prints one slug on stdout; exit 2 (non-ASCII input) or exit 3 (empty slug) → re-translate the title into an English phrase and retry, never hand-build the branch name.
+   4. Run `git checkout -b {target branch} origin/{base branch}` so the branch starts at the remote base, then bring step 1's commits onto it (`git cherry-pick` them when they landed on another branch). Done when `git branch --show-current` prints the target branch and `git log --oneline origin/{base branch}..HEAD` lists exactly step 1's commits.
+4. Run `git push -u origin {target branch}`. Done when `git ls-remote --heads origin` shows the target branch's ref.
 5. Create the PR: `jsc-gitea/tools/gitea.sh pr-create {owner}/{repo} {target branch} {base branch} "{branch name}" {description file}`.
    - Title = branch name.
    - Write the description into a temp file first, using `templates/pr-description.md` (a Traditional Chinese template; the generated description stays in Traditional Chinese per the STE100 output rule).
+   - Done when the command prints a PR URL; no URL → report the error and stop.
 6. **Prerequisite PR blocking**: when the description lists a prerequisite Push Request, run
    `jsc-gitea/tools/gitea.sh pr-depend {owner}/{repo} {this PR number} {prerequisite owner}/{repo} {prerequisite PR number}`
-   to add the dependency. Gitea then blocks merging until the prerequisite PR closes. If the API is unavailable, degrade: prefix the PR title with `WIP:` (Gitea blocks merging natively) and remove it once the prerequisite is done.
-7. Report the PR URL.
+   to add the dependency. Gitea then blocks merging until the prerequisite PR closes. On exit 4 (the dependency API call failed) degrade: prefix the PR title with `WIP:`, which Gitea blocks merging on natively, and record in the PR description that the prefix comes off once the prerequisite PR closes. Done when `pr-depend` printed `OK {owner}/{repo}#{number} depends on ...`, or the PR title starts with `WIP:` and the description names the prerequisite PR.
+7. Report the PR URL. Done when the reported URL is the one step 5 printed, together with the base branch and the target branch it was opened against.
 
 ## Rules
 
 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.
+2. Read the `jsc-sdlc` plan page and analyze page through `jsc-gitea:wiki`, which resolves `JSC_WIKI_REPO_PLAN` for the plan page and `JSC_WIKI_REPO_ANALYZE` for the analyze page from the inherited environment, falls back to `JSC_WIKI_REPO`, and asks only when neither is set. Each page type reads its own variable only; a page type never borrows another type's variable. Take both links from the pages read this way; the analyze link must point at the work package heading anchor.
 3. Branch title summarization (step 3.2) and description drafting MUST run as a sub agent.