YQL-16277: Implement ExpandSqlCombine optimizer

#### Implement SqlCombine optimizer and enhance ListJoinCore type checking ✎

- Introduce ExpandSqlCombine optimizer to handle SQL COMBINE operations, enabling efficient execution of combine operations with proper key handling and sorting
- Refactor ListJoinCore type annotation logic to use tuples instead of structs for key types, improving type safety and consistency in multi-key scenarios
- Add auxiliary constants for consistent naming of input prefixes and key members in join operations
- Update MKQL compiler and type annotation components to support the new SqlCombine expansion and improved type checking
- Enhance test coverage with new test cases for various SqlCombine scenarios including single key, multi-key, optional keys, and type mismatches
- Adjust existing tests and canonical data to reflect the changes in type handling and naming conventions

<a href="https://nda.ya.ru/t/qa0kX64r7DqvtN"><font size="2">Autodescription by Yandex Code Assistant</font></a>
commit_hash:376f67bfed851d0e4f7ac354d22220ba4f4737e2

0 files changed, 0 insertions, 0 deletions