fix: canonicalize sliced VarBinArray failure

[a10y]

A user report came in with the following stacktrace:

                 at /usr/local/cargo/registry/src/index.crates.io-1949cf8c6b5b557f/arrow-array-56.2.0/src/builder/generic_bytes_view_builder.rs:176:9
      12: <arrow_array::array::byte_view_array::GenericByteViewArray<V> as core::convert::From<&arrow_array::array::byte_array::GenericByteArray<FROM>>>::from
                 at /usr/local/cargo/registry/src/index.crates.io-1949cf8c6b5b557f/arrow-array-56.2.0/src/array/byte_view_array.rs:913:39
      13: vortex_array::arrays::varbin::vtable::canonical::<impl vortex_array::vtable::canonical::CanonicalVTable<vortex_array::arrays::varbin::vtable::VarBinVTable> for vortex_array::arrays::varbin::vtable::VarBinVTable>::canonicalize
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-array/src/arrays/varbin/vtable/canonical.rs:38:26
      14: <vortex_array::array::ArrayAdapter<V> as vortex_array::array::Array>::to_canonical
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-array/src/array/mod.rs:609:25
      15: <A as vortex_array::canonical::ToCanonical>::to_varbinview
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-array/src/canonical.rs:374:14
      16: <vortex_array::builders::varbinview::VarBinViewBuilder as vortex_array::builders::ArrayBuilder>::extend_from_array_unchecked
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-array/src/builders/varbinview.rs:278:27
      17: <vortex_array::builders::fixed_size_list::FixedSizeListBuilder as vortex_array::builders::ArrayBuilder>::extend_from_array_unchecked
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-array/src/builders/fixed_size_list.rs:243:31
      18: vortex_array::stats::array::StatsSetRef::compute_stat
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-array/src/stats/array.rs:177:29
      19: vortex_array::stats::array::StatsSetRef::compute_all
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-array/src/stats/array.rs:200:35
      20: <vortex_layout::layouts::compressed::CompressingStrategy as vortex_layout::strategy::LayoutStrategy>::write_stream::{{closure}}::{{closure}}::{{closure}}
                 at /usr/local/cargo/git/checkouts/vortex-e8ac85adeb77362c/f1b2ae9/vortex-layout/src/layouts/compressed.rs:144:26

The failure is inside of arrow-rs, in its conversion from LargeStringArray -> StringViewArray.

Arrow checks that the final offset is < i32::MAX, and then pushes the buffer. This will not work if we're trying to convert a large VarBinArray that's been sliced, so that the final offset is not the maximum size of the buffer.

Upstream arrow-rs should get a fix as well, but in the meantime, this should fix the behavior of compressing large chunks, by rezeroing offsets before we canonicalize VarBin.

[a10y]

i can't check this in because it's too slow, but this was failing before and now it's not (you actually need to update VarBinArray::from_iter_nonnull to use u64 offsets to make it pass)

[joseph-isaacs]

can we not use the slow run on post commit?

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing varbin-arrow-fix (23f6f86) with develop (4bbafe7)}

Summary

✅ 1254 untouched benchmarks
⏩ 1254 skipped benchmarks¹

Footnotes

1. 1254 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[codecov]

Codecov Report

❌ Patch coverage is 85.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 82.88%. Comparing base (4bbafe7) to head (23f6f86).
⚠️ Report is 1 commits behind head on develop.

Files with missing lines	Patch %	Lines
vortex-array/src/arrays/varbin/array.rs	83.33%	3 Missing ⚠️

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[a10y]

now that we slice before canonicalizing, we write fewer segments of the string column, which results in fewer splits getting planned, so this is no longer true.

the test is just updated to make sure the sum of the fragment row counts matches the expected row count after the filter