perf: optimise right for byte access and StringView

[theirix]

Which issue does this PR close?

• Closes perf: optimise right for byte access and StringView #20068.

Rationale for this change

Similar to issue #19749 and the optimisation of left in #19980, it's worth doing the same for right

What changes are included in this PR?

• Improve efficiency of the function by making fewer memory allocations and going directly to bytes, based on char boundaries

• Provide a specialisation for StringView with buffer zero-copy

• Use arrow_array::buffer::make_view for low-level view manipulation (we still need to know about a magic constant 12 for a buffer layout)

• Benchmark - up to 90% performance improvement

right size=1024/string_array positive n/1024
                        time:   [24.286 µs 24.658 µs 25.087 µs]
                        change: [−86.881% −86.662% −86.424%] (p = 0.00 < 0.05)
                        Performance has improved.
right size=1024/string_array negative n/1024
                        time:   [29.996 µs 30.737 µs 31.511 µs]
                        change: [−89.442% −89.229% −89.003%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 1 outliers among 100 measurements (1.00%)
  1 (1.00%) high mild

right size=4096/string_array positive n/4096
                        time:   [105.58 µs 109.39 µs 113.51 µs]
                        change: [−86.119% −85.788% −85.497%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 9 outliers among 100 measurements (9.00%)
  6 (6.00%) high mild
  3 (3.00%) high severe
right size=4096/string_array negative n/4096
                        time:   [136.48 µs 138.34 µs 140.36 µs]
                        change: [−88.007% −87.848% −87.692%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 4 outliers among 100 measurements (4.00%)
  4 (4.00%) high mild

right size=1024/string_view_array positive n/1024
                        time:   [25.054 µs 25.500 µs 26.033 µs]
                        change: [−82.569% −82.285% −81.891%] (p = 0.00 < 0.05)
                        Performance has improved.
right size=1024/string_view_array negative n/1024
                        time:   [41.281 µs 42.730 µs 44.432 µs]
                        change: [−73.832% −73.288% −72.716%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 5 outliers among 100 measurements (5.00%)
  3 (3.00%) high mild
  2 (2.00%) high severe

right size=4096/string_view_array positive n/4096
                        time:   [129.38 µs 133.69 µs 137.61 µs]
                        change: [−79.497% −78.998% −78.581%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 4 outliers among 100 measurements (4.00%)
  4 (4.00%) high mild
right size=4096/string_view_array negative n/4096
                        time:   [218.16 µs 229.41 µs 243.30 µs]
                        change: [−65.405% −63.622% −61.515%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 10 outliers among 100 measurements (10.00%)
  3 (3.00%) high mild
  7 (7.00%) high severe

Are these changes tested?

• Existing unit tests for right

• Added more unit tests

• Added bench similar to right.rs

• Existing SLTs pass

Are there any user-facing changes?

No

[theirix]

cc @Jefffrey

[Jefffrey]

I haven't looked too closely, but I feel we can deduplicate right + left implementation code as the main difference is this byte length function? In that it flips which side it looks from?

[Jefffrey]

Commented code accidentally added here