Add kh_replace function that uses direct memory copying instead of
element-by-element rehashing for improved performance.
- Add kh_replace_name function with smart handling of different table types
- Optimize kh_copy to use kh_replace instead of element iteration
- Update Set operations to use kh_replace for copying
- Remove redundant kset_copy_replace function
The optimization provides O(1) memory copy vs O(n) hash operations,
handles small tables and hash tables correctly, and avoids infinite
recursion issues with self-referential data structures.
Co-authored-by: Claude <noreply@anthropic.com>
Yukihiro "Matz" Matsumoto
7368be7568