Fix nested scalar hashing

[connortsui20]

Fixes #8744

Scalar equality ignores dtype nullability recursively, but hashing only removed top-level nullability. The typed scalar views had the same mismatch, so equal nested values could produce different hashes.

• adds recursive nullability-insensitive dtype hashing matching DType::eq_ignore_nullability
• uses it for Scalar, ListScalar, StructScalar, and ExtScalar
• covers nested list, struct, Union dtype, and extension storage nullability regressions

This is kind of ugly but I don't think there is a better way to do this

[codecov]

Codecov Report

❌ Patch coverage is 95.65217% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.82%. Comparing base (17f843a) to head (76745ac).
⚠️ Report is 1 commits behind head on develop.

Files with missing lines	Patch %	Lines
vortex-array/src/dtype/dtype_impl.rs	87.50%	6 Missing ⚠️

☔ View full report in Codecov by Harness.
📢 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.

[github-actions]

Polar Signals Profiling Results

Latest Run

Status	Commit	Job	Attempt	Link
🟢 Done	76745ac		1	Explore Profiling Data

---

Powered by Polar Signals Cloud

[github-actions]

Benchmarks: Vortex queries

Verdict: No clear signal (low confidence)
Attributed Vortex impact: +5.6%
Engines: DataFusion Likely regression (+12.6%, medium confidence) · DuckDB No clear signal (-0.9%, low confidence)
Vortex (geomean): 1.008x ➖
Parquet (geomean): 0.981x ➖
Shifts: Parquet (control) -1.9% · Median polish +1.1%

How to read Verdict and Engines

• Verdict: Overall PR-level signal after subtracting baseline drift estimated from Parquet control rows. It can be Likely improvement, Likely regression, or No clear signal.
• Engines: Per-engine attribution. DataFusion is compared against DataFusion/Parquet controls; DuckDB is compared against DuckDB/Parquet controls. This answers whether each engine improved or regressed independently.
• Confidence: Based on directional consistency, share of rows above the noise floor, and control-run noise.

---

datafusion / vortex-file-compressed (1.067x ➖, 0↑ 0↓)

name	PR 76745ac (ns)	base 17f843a (ns)	ratio (PR/base)
vortex_q00/datafusion:vortex-file-compressed	10302567	9877069	1.04
vortex_q01/datafusion:vortex-file-compressed	6927132	6345790	1.09

datafusion / parquet (0.948x ➖, 0↑ 0↓)

name	PR 76745ac (ns)	base 17f843a (ns)	ratio (PR/base)
vortex_q00/datafusion:parquet	20891906	21920309	0.95
vortex_q01/datafusion:parquet	4840236	5135545	0.94

duckdb / vortex-file-compressed (1.007x ➖, 0↑ 0↓)

name	PR 76745ac (ns)	base 17f843a (ns)	ratio (PR/base)
vortex_q00/duckdb:vortex-file-compressed	10738963	10602435	1.01
vortex_q01/duckdb:vortex-file-compressed	6564743	6559583	1.00

duckdb / parquet (1.016x ➖, 0↑ 0↓)

name	PR 76745ac (ns)	base 17f843a (ns)	ratio (PR/base)
vortex_q00/duckdb:parquet	23928956	23596214	1.01
vortex_q01/duckdb:parquet	9711741	9543018	1.02

---

No file size changes detected.