Make struct cast implementation pluggable

[robert3005]

This pr moves Struct Cast implementation to be overridable by VortexSession.

The default implementation stays the same, i.e. it resolves the fields by name.

In follow up we will add back the positional cast and add both implementations
to the fuzzer

Signed-off-by: Robert Kruszewski github@robertk.io

[codspeed-hq]

Merging this PR will degrade performance by 18.01%

⚠️ 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.

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
❌ 2 regressed benchmarks
✅ 378 untouched benchmarks
⏩ 817 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	mix[0%_in/100%_out]	228.4 µs	278.5 µs	-18.01%
⚡	WallTime	10M_50%[5000000]	308.7 µs	278 µs	+11.05%
❌	Simulation	bitwise_not_vortex_buffer_mut[128]	246.1 ns	275.3 ns	-10.6%

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_{Comparing rk/movecasttoplugin (b2b9997) with develop (6d2aee8)}

Footnotes

1. 817 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. ↩

[connortsui20]

Is this related to #6900?

[robert3005]

It is related. We need to acknowledge that different systems have different requirements and we need to be able to override the behaviour

[robert3005]

as I was refactoring this logic I made #7710 to cleanup validity casting