[fix] extend sort by to include bucket_size

[dot2dotseurat]

Hi, Dune uses typesense-utils and we'd like to start using bucket_size in our sorting.

The new parameter, bucket_size, was introduced in v28

Changes

• Added support for $bucket_size parameter in SortByTextMatch interface
• Added new test case to verify $bucket_size functionality
• Extended the next function to handle $bucket_size parameter in sort expressions

Testing

• Added test case that verifies correct generation of sort expression with bucket_size:3
• Test ensures proper integration with existing sort parameters like $order

[dot2dotseurat]

@igrek8 do you have some time to review this or is there someone else I should request a review from

[igrek8]

Hello @dot2dotseurat, version npm i typesense-utils@1.1.0 has been released with bucket_size param support. Closing this PR. https://github.com/igrek8/typesense-utils/blob/main/src/buildSortBy.test.ts#L32