Implement ADD_SWITCHER keyword following the same pattern as ADD_SUGGESTION_TOOL:
- Created switcher.rs module with add_switcher_keyword() and clear_switchers_keyword()
- Added preprocessing to convert "ADD SWITCHER" to "ADD_SWITCHER"
- Added to keyword patterns and get_all_keywords()
- Stores switcher suggestions in Redis with type "switcher" and action "switch_context"
- Supports both "ADD SWITCHER" and "ADD_SWITCHER" syntax
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Co-Authored-By: Claude <noreply@anthropic.com>