feat(狀態回報): 收尾寫一筆 skill-end 事件

現行紀錄只記「被叫用」，沒有成敗也沒有結束碼。跑完整輪的技能與開場就
中止的技能，在紀錄裡長得一模一樣。

start 由技能用量 hook 順手發，不必改技能文件。end 只能由技能自己在收尾
步驟寫——hook 接在技能工具呼叫上，而實際工作發生在之後的模型輪次，它在
原理上看不到成敗。有 start 沒有配對的 end，就是那一輪中止了。

status 五選一，每支技能各自寫明什麼情況選哪一個。找不到回報腳本就安靜
跳過，回報失敗一律不改變技能自己的結論。

skills/html-export/SKILL.md

@@ -19,6 +19,21 @@ The link is the only input. The output is one file that opens anywhere, with no
    Completion condition: the markdown and the document title are in hand, exactly one kind key is chosen with the reason that produced it, the layout, style and source are reported, and the user has confirmed one output path.
 4. **Prepare the markdown — this step MUST run as a sub agent.** Links are written as `[text](absolute URL)`, so pages that follow the current rule need no conversion. An older page can still carry a wiki-internal link: turn it into an absolute URL from `wiki-url`, because the renderer does not resolve it and it would ship as literal brackets. Strip personal data — an exported file travels further than the page it came from. Leave everything else exactly as written; this step never rewrites the content. Completion condition: every link in the file is `[text](absolute URL)`, and the diff against the source is limited to link conversion and personal-data removal.
 5. Render: `tools/html-render.sh --markdown {file} --title {title} --layout {layout} --style {style} --source-url {absolute URL} --out {path}`. Route every exit code: 0 → the path it printed is the finished file; 1 → Gitea's renderer or the write failed, so report it and stop, with no half-rendered file left behind; 2 → a usage error or a missing markdown file, so fix the arguments and call again; 4 → the layout or style template file is gone, so report which pair was asked for and send the user to `jsc-gitea:html-style` rather than editing the configuration by hand. Completion condition: the file exists, and the report names its path, the layout, the style and where that pair came from.
+6. **Record how the run ended.** This is the last thing this skill does, and it runs on every path out of the skill — including the ones that stop at step 1. Call
+
+   `jsc-hooks/tools/report-status.sh skill-end jsc-gitea:html-export {status} {exit code} [detail]`
+
+   `{exit code}` is the exit code of whatever decided the outcome, and `0` when nothing failed. `{detail}` is one short line, no more than 200 characters. **If the script is not on this machine, skip this step in silence and finish the run as it stood** — missing infrastructure is not a failure, and a reporting call may never change what this skill returns or reports.
+
+   | status | When this skill uses it |
+   | --- | --- |
+   | `ok` | The file was rendered and the report names its path, layout, style and source |
+   | `blocked` | The host gate of step 2 stopped the run: `GITEA_HOST` holds no value and the user gave none, so nothing was read and nothing was rendered |
+   | `failed` | The work started and broke: `wiki-get` returned 7 or 8, `issue.sh show` returned 1, or `html-render.sh` returned 1, 2 or 4. Nothing usable came out |
+   | `degraded` | The file was rendered, but part of the run did not hold — track B could not read the labels (exit 1) so the template was picked without them, and the export used a template the configuration did not choose |
+   | `aborted` | The premise did not hold, so the skill stopped on its own: the request carried no wiki or issue link, or `gitea-link.sh parse` returned 3. Also used when the user stops the run at step 3's destination question |
+
+   Completion condition: exactly one `skill-end` line was recorded for this run, or the script was absent and the run finished without it.
 
 ## Rules