fix(rating): half star focus management and roving navigation (#192)

* fix(rating): improve half-step navigation and focus behavior

- Fix roving navigation to focus correct item for half-step values (e.g., 3.5 stars)
- Prevent half-step values from rounding up on focus
- Make arrow keys increment/decrement by step value (0.5) instead of jumping full items

* fix(rating): improve half-step navigation and refactor store pattern

- Fix roving navigation to focus correct item for half-step values (e.g., 3.5 stars focuses 4th item)
- Prevent half-star values from becoming full stars on focus in automatic mode
- Update arrow key navigation to increment/decrement by step value (0.5) instead of jumping to next item
- Refactor store creation to inline pattern with useAsRef for stable callbacks
- Apply useAsRef to RatingRootImpl props to prevent unnecessary context recreations
- Reorganize type definitions for better code structure
- Improve performance by reducing unnecessary re-renders

* chore: rebuild registry

Author: sadmann7