docs(zh): escape pipe in command table

[GeoDaoyu]

Description

fix #74

Type of Change

• New example or template
• Documentation improvement
• Bug fix
• Feature guide
• Other (please describe)

Related Issues

Closes #74

Changes Made

• escape pipe in command table

What to Review

Table's content.

Files Changed

• zh/01-slash-commands/README.md

Testing

How have you tested this?

• Tested locally with Claude Code
• Verified examples work
• Checked links and references
• Reviewed for typos and clarity

Checklist

• Follows project structure and conventions
• Includes clear documentation/examples
• Code/examples are copy-paste ready
• All links are verified and working
• No sensitive information included (keys, tokens, credentials)
• Updated relevant README files
• Commit message follows conventional commit format
• No large files (>1MB) added

Screenshots or Examples

If applicable, show what this adds:

| `/color [color\|default]` | 设置提示栏颜色 |

Breaking Changes

Does this change any existing content or behavior?

• No breaking changes
• Yes, and it's documented below

Additional Notes

No