* feat: add optional mode field to slash command front matter
- Add mode field to Command interface
- Update command parsing to extract mode from frontmatter
- Modify RunSlashCommandTool to automatically switch mode when specified
- Add comprehensive tests for mode field parsing and switching
- Update existing tests to include mode field
* Make it work for manual slash commands too
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Co-authored-by: Roo Code <roomote@roocode.com>
Co-authored-by: Matt Rubens <mrubens@users.noreply.github.com>
