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

.github/skills/gh-issue-replier/references/example_reference.md

@@ -0,0 +1,17 @@
+# Reference Documentation for Gh Issue Replier
+
+This is a placeholder for detailed reference documentation.
+Replace with actual reference content or delete if not needed.
+
+## Structure Suggestions
+
+### API Reference Example
+- Overview
+- Authentication
+- Endpoints with examples
+- Error codes
+
+### Workflow Guide Example
+- Prerequisites
+- Step-by-step instructions
+- Best practices