perf(arrow/array): concatenate list offsets directly

[fallintoplace]

What

• Concatenate List and LargeList offsets directly into the output buffer.

Why

• Avoid temporary fixed-width buffer wrappers for every input chunk.
• Improve concatenation when arrays are split into many chunks.

Implementation

• Added concatOffsetsData using the existing direct 32-bit and 64-bit offset handlers.
• Updated only the List and LargeList paths. Map and Binary paths are unchanged.
• Added a benchmark covering both list types and 64, 1,024, and 8,192 chunks.

Benchmark on an Apple M1 Pro with 65,536 values:

Case	ns/op before -> after	allocs/op before -> after
List, 64 chunks	86.5us -> 82.3us	211 -> 145
List, 1,024 chunks	274.1us -> 229.5us	3,309 -> 2,273
List, 8,192 chunks	1.512ms -> 1.220ms	28,627 -> 19,656
LargeList, 64 chunks	93.7us -> 87.5us	211 -> 146
LargeList, 1,024 chunks	262.6us -> 222.5us	3,297 -> 2,254
LargeList, 8,192 chunks	1.467ms -> 1.192ms	28,244 -> 19,217

Tests:

• go test ./arrow/array -count=1
• go vet ./arrow/array
• git diff --check