docs: update Last Updated date and Claude Code version across all files

Update all documentation footers from generic "April 2026 / 2.1+" to
the specific sync date (April 9, 2026) and documented version (2.3.0).
Also add version/date footers to zh/CATALOG.md and
zh/01-slash-commands/README.md which were missing them.

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

01-slash-commands/README.md

@@ -558,8 +558,8 @@ If both exist with the same name, the **skill takes precedence**. Remove one or
 - [CLI Reference](https://code.claude.com/docs/en/cli-reference) - Command-line options
 
 ---
-**Last Updated**: April 2026
-**Claude Code Version**: 2.1+
+**Last Updated**: April 9, 2026
+**Claude Code Version**: 2.3.0
 **Compatible Models**: Claude Sonnet 4.6, Claude Opus 4.6, Claude Haiku 4.5
 
 *Part of the [Claude How To](../) guide series*

01-slash-commands/commit.md

@@ -26,4 +26,4 @@ Otherwise, analyze the changes and create an appropriate commit message followin
 - `chore:` for maintenance tasks
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026

01-slash-commands/doc-refactor.md

@@ -24,4 +24,4 @@ Refactor project documentation structure adapted to project type:
 Keep docs concise, scannable, and contextual to project type.
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026

01-slash-commands/generate-api-docs.md

@@ -19,4 +19,4 @@ Output format:
 - Add TypeScript types
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026

01-slash-commands/optimize.md

@@ -19,4 +19,4 @@ Format your response with:
 - Recommended fix with code example
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026

01-slash-commands/pr.md

@@ -26,4 +26,4 @@ Before creating a PR, execute these steps:
    - Potential impacts
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026

01-slash-commands/push-all.md

@@ -152,4 +152,4 @@ If user wants control, suggest:
 **⚠️ Remember**: Always review changes before pushing. When in doubt, use individual git commands for more control.
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026

01-slash-commands/setup-ci-cd.md

@@ -25,4 +25,4 @@ Implement comprehensive DevOps quality gates adapted to project type:
 Use free/open-source tools. Respect existing configs. Keep execution fast.
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026

01-slash-commands/unit-test-expand.md

@@ -25,4 +25,4 @@ Expand existing unit tests adapted to project's testing framework:
 Present new test code blocks only. Follow existing test patterns and naming conventions.
 
 ---
-**Last Updated**: April 2026
+**Last Updated**: April 9, 2026