…4634)

This commit refactors the native vector scoring templates so that mapper functions return a direct `const T*` pointer to the target vector, instead of an `int64_t` byte offset that callers then multiply and add to a base pointer. This simplifies every bulk scoring template (`call_i8_bulk`, `call_f32_bulk`, `cosi8_inner_bulk`, `dot7u_inner_bulk`, `sqr7u_inner_bulk`, `doti4_bulk_impl`, `dotdXq4_inner_bulk`) by collapsing the three-step resolve-offset-then-compute-pointer pattern into a single mapper call.

Specifically:
- **`vec_common.h`**: `identity_mapper` and `array_mapper` are now templates returning `const T*`. Removed `safe_mapper_offset` and `init_offsets`; replaced with `init_pointers` which combines pointer resolution and bounds checking in one step.
- **aarch64 and amd64 `.cpp` files**: Updated all template signatures, mapper call sites, and `init_offsets` /
    `safe_mapper_offset` usages to use the new pointer-returning mappers and `init_pointers`.

Motivation

The previous design required each call site to perform `base + mapper(i, offsets) * pitch` to obtain a vector pointer. With mappers returning pointers directly, call sites are simpler and the mapper signature becomes extensible; new mappers (e.g. for non-contiguous memory layouts) can use completely different addressing strategies while conforming to the same function pointer type. We have such things in the works!

PR elastic#144634 refactored mappers to return pointers directly
instead of indices. Update vec_i4_2.cpp to use the new
init_pointers, sequential_mapper, and offsets_mapper.

Made-with: Cursor

Follow-up to #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.

…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.