Add extension storage scalar function

[gatesn]

This function allows you to extract the storage value from an extension type.

It is safe for us to generically implement this, but for casting storage -> extension type it should be custom kernels to perform validation etc.

[codspeed-hq]

Merging this PR will not alter performance

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚡ 9 improved benchmarks
❌ 4 regressed benchmarks
✅ 1568 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	chunked_bool_canonical_into[(1000, 10)]	20.2 µs	29 µs	-30.19%
❌	Simulation	chunked_varbinview_into_canonical[(1000, 10)]	169.5 µs	205.6 µs	-17.57%
❌	Simulation	decompress_rd[f64, (100000, 0.0)]	843.2 µs	978.9 µs	-13.87%
❌	Simulation	varbinview_large	112.2 µs	130.2 µs	-13.78%
⚡	Simulation	chunked_varbinview_canonical_into[(1000, 10)]	191 µs	154.4 µs	+23.67%
⚡	Simulation	chunked_varbinview_opt_canonical_into[(1000, 10)]	206.7 µs	170.5 µs	+21.25%
⚡	Simulation	chunked_varbinview_opt_into_canonical[(1000, 10)]	221.4 µs	184.8 µs	+19.81%
⚡	Simulation	decompress_rd[f64, (100000, 0.01)]	978.3 µs	842.4 µs	+16.13%
⚡	Simulation	chunked_varbinview_canonical_into[(100, 100)]	258.7 µs	223.5 µs	+15.74%
⚡	Simulation	chunked_varbinview_into_canonical[(100, 100)]	308 µs	271.5 µs	+13.43%
⚡	Simulation	bitwise_not_vortex_buffer_mut[128]	273.6 ns	244.4 ns	+11.93%
⚡	Simulation	chunked_varbinview_opt_canonical_into[(100, 100)]	338.2 µs	304.5 µs	+11.08%
⚡	Simulation	eq_i64_constant	318.3 µs	288.9 µs	+10.15%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing ngates/ext-storage-scalar-function (8f664ff) with develop (e7a7ad9)}