This PR adds BULK_SPARSE native exports for BBQ (d1q4, d2q4, d4q4) and packed INT4 vector dot-product operations on both amd64 and aarch64. This fills out BULK_SPARSE support for these element types, consistent with INT7U and INT8 which already have sparse operations.

Unlike BULK_OFFSETS, which requires all vectors to reside in a single contiguous memory region, BULK_SPARSE accepts an array of independent memory addresses, one per vector. This enables efficient bulk scoring over scatter-gather data, such as when vectors are backed by DirectAccessInput with its 16MiB region boundaries.

The new native functions use the sparse_mapper with the generalized TData bulk templates introduced in #145459. JdkVectorLibrary is updated to enable BULK_SPARSE for BBQ and INT4 with appropriate bounds checking, and Similarities gains corresponding method handles and Java wrapper methods. Unit tests cover contiguous slices, scattered (non-contiguous) allocations, and illegal argument validation for both BBQ (parameterized across d1q4, d2q4, d4q4) and INT4.

…145459)

Follow-up to elastic#144634. Extends the TData mapper template generalization to the BBQ (dotd1q4, dotd2q4, dotd4q4) and INT4 (doti4) bulk scoring templates on both amd64 and aarch64 tier-1, which were not covered by the original refactoring.

This is a pure refactor with no functional change. The existing sequential_mapper and offsets_mapper instantiations now explicitly pass int8_t as TData rather than hardcoding const int8_t* in the template signature.

…5676)

This PR adds BULK_SPARSE native exports for BBQ (d1q4, d2q4, d4q4) and packed INT4 vector dot-product operations on both amd64 and aarch64. This fills out BULK_SPARSE support for these element types, consistent with INT7U and INT8 which already have sparse operations.

Unlike BULK_OFFSETS, which requires all vectors to reside in a single contiguous memory region, BULK_SPARSE accepts an array of independent memory addresses, one per vector. This enables efficient bulk scoring over scatter-gather data, such as when vectors are backed by DirectAccessInput with its 16MiB region boundaries.

The new native functions use the sparse_mapper with the generalized TData bulk templates introduced in elastic#145459. JdkVectorLibrary is updated to enable BULK_SPARSE for BBQ and INT4 with appropriate bounds checking, and Similarities gains corresponding method handles and Java wrapper methods. Unit tests cover contiguous slices, scattered (non-contiguous) allocations, and illegal argument validation for both BBQ (parameterized across d1q4, d2q4, d4q4) and INT4.