chore(skills): sync .gemini and .github skills and fix i18n validator

.github/skills/version-bumper/SKILL.md

@@ -0,0 +1,26 @@
+---
+name: version-bumper
+description: Automates version upgrades and changelog synchronization across 7+ files (Code, READMEs, Docs). Use when a plugin is ready for release to ensure version consistency.
+---
+
+# Version Bumper
+
+## Overview
+This skill ensures that every version upgrade is synchronized across the entire repository, following the strict "Documentation Sync" rule in GEMINI.md.
+
+## Workflow
+1. **Prepare Info**: Gather the new version number and brief changelogs in both English and Chinese.
+2. **Auto-Patch**: The skill will help you identify and update:
+   - `plugins/.../name.py` (docstring version)
+   - `plugins/.../README.md` (metadata & What's New)
+   - `plugins/.../README_CN.md` (metadata & 最新更新)
+   - `docs/plugins/...md` (mirrors)
+   - `docs/plugins/index.md` (version badge)
+   - `README.md` (updated date badge)
+3. **Verify**: Check the diffs to ensure no formatting was broken.
+
+## Tool Integration
+Execute the bump script (draft):
+```bash
+python3 scripts/bump.py <version> "<message_en>" "<message_zh>"
+```