feat(ci): add skill release commit validation

Add CI check to ensure commits touching skills/<name>/** use
Conventional Commit subjects. Also validates SKILL.md version
alignment during publish/sync.

scripts/lib/skill-release-guard.test.ts

@@ -0,0 +1,69 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import {
+  changedSkillsForPaths,
+  formatSkillReleaseFailures,
+  parseConventionalCommitSubject,
+  validateSkillReleaseCommit,
+} from "./skill-release-guard.mjs";
+
+test("parseConventionalCommitSubject accepts scoped, unscoped, and breaking subjects", () => {
+  assert.deepEqual(parseConventionalCommitSubject("fix(baoyu-post-to-wechat): repair editor paste"), {
+    type: "fix",
+    scope: "baoyu-post-to-wechat",
+    breaking: false,
+    description: "repair editor paste",
+  });
+  assert.deepEqual(parseConventionalCommitSubject("feat!: change skill metadata format"), {
+    type: "feat",
+    scope: "",
+    breaking: true,
+    description: "change skill metadata format",
+  });
+  assert.equal(parseConventionalCommitSubject("Fix WeChat browser article publishing"), null);
+});
+
+test("changedSkillsForPaths returns sorted unique skills", () => {
+  assert.deepEqual(
+    changedSkillsForPaths([
+      "README.md",
+      "skills/baoyu-post-to-wechat/scripts/wechat-article.ts",
+      "skills/baoyu-post-to-wechat/SKILL.md",
+      "skills/baoyu-url-to-markdown/SKILL.md",
+    ]),
+    ["baoyu-post-to-wechat", "baoyu-url-to-markdown"],
+  );
+});
+
+test("validateSkillReleaseCommit ignores non-skill changes", () => {
+  assert.deepEqual(
+    validateSkillReleaseCommit({
+      subject: "Fix test workflow",
+      paths: [".github/workflows/test.yml"],
+    }),
+    [],
+  );
+});
+
+test("validateSkillReleaseCommit rejects non-conventional skill commit subjects", () => {
+  const failures = validateSkillReleaseCommit({
+    commit: "81377416b4a7",
+    subject: "Fix WeChat browser article publishing",
+    paths: ["skills/baoyu-post-to-wechat/scripts/wechat-article.ts"],
+  });
+
+  assert.equal(failures.length, 1);
+  assert.match(failures[0]!.message, /Conventional Commit/);
+  assert.match(formatSkillReleaseFailures(failures), /fix\(baoyu-post-to-wechat\):/);
+});
+
+test("validateSkillReleaseCommit accepts conventional skill commit subjects", () => {
+  assert.deepEqual(
+    validateSkillReleaseCommit({
+      subject: "fix(browser): ensure tab activation before copy/paste in WeChat editor",
+      paths: ["skills/baoyu-post-to-wechat/scripts/wechat-article.ts"],
+    }),
+    [],
+  );
+});