- Organize COMMANDS into COMMANDS_BY_CATEGORY dict
- Group commands: Session, Configuration, Tools & Skills, Info, Exit
- Add visual category headers with spacing
- Maintain backwards compat via flat COMMANDS dict
- Better visual hierarchy and scannability
Before:
/help - Show this help message
/tools - List available tools
... (dense list)
After:
── Session ──
/new Start a new conversation
/reset Reset conversation only
...
── Configuration ──
/config Show current configuration
...
Closes#640