Deprecate FromArrowArray in favour of ArrowSession array imports

[robert3005]

Rationale for this change

Stacked on #8918. Second step of making ArrowSession the authoritative Arrow ⇄ Vortex conversion API: this PR deprecates the array-import traits (FromArrowArray; IntoArrowArray was already deprecated and has no remaining users) and migrates every usage to session methods.

What changes are included in this PR?

• FromArrowArray is #[deprecated], and each of its impl bodies is extracted into a named, directly invocable function in vortex_arrow::convert (from_arrow_primitive, from_arrow_decimal*, from_arrow_temporal, from_arrow_bytes, from_arrow_byte_view, from_arrow_boolean, from_arrow_struct, from_arrow_list, from_arrow_list_view, from_arrow_fixed_size_list, from_arrow_null, from_arrow_dictionary, from_arrow_run_array, from_arrow_dyn, from_arrow_batch). The trait impls are thin shims over these, so the trait can eventually be deleted.
• ArrowSession gains from_arrow_array_nullable(&dyn Array, nullable) — the field-less import. No top-level extension dispatch is possible without a Field, but nested container fields still route through registered import plugins.
• ArrowImportVTable::from_arrow_array now receives &ArrowSession (mirroring from_arrow_field from Deprecate all non ArrowSession DType imports and exports #8918); the uuid, geo (×8), json, tensor, and parquet-variant plugins convert their storage through the session.
• The session is threaded as an argument everywhere — no default-session statics: ParquetVariant::from_arrow_variant{,_nullable} take &ArrowSession (from vtables/kernels), native_geometry_scalar_from_wkb takes &ArrowSession (vortex-duckdb passes its crate session), and vx_array_from_arrow takes a const vx_session* and imports through the FFI schema's Field, so Arrow extension types round-trip.
• All consumers migrated: vortex-datafusion, vortex-python, vortex-ffi, vortex-tui, vortex-bench, compat-gen, vortex-layout, and the [convert] doc snippet in the vortex facade. RecordBatch imports now go through ArrowSession::from_arrow_record_batch, keeping array dtypes consistent with the session-derived schemas from Deprecate all non ArrowSession DType imports and exports #8918.

What APIs are changed? Are there any user-facing changes?

• FromArrowArray (trait + method) is deprecated; replacements are ArrowSession::{from_arrow_array, from_arrow_array_nullable, from_arrow_record_batch} and the typed vortex_arrow::convert::from_arrow_* functions.
• ArrowImportVTable::from_arrow_array gains a session: &ArrowSession parameter (breaking for plugin implementors).
• ParquetVariant::from_arrow_variant and vortex_geo::extension::native_geometry_scalar_from_wkb gain a session parameter; vx_array_from_arrow gains a const vx_session* parameter (C header regenerated).

🤖 Generated with Claude Code

[codspeed-hq]

Merging this PR will not alter performance

✅ 1849 untouched benchmarks
⏩ 46 skipped benchmarks¹

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_{Comparing rk/deprecate-arrow-arrays (154677c) with rk/deprecate (452e451)²}

Footnotes

1. 46 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. ↩

2. No successful run was found on rk/deprecate (8adb394) during the generation of this report, so 0d65210 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩