ffi: expose array validity, allow creating primitive arrays #7148

Performance Regression: -15.51%

❌ 3 regressed benchmarks
✅ 1098 untouched benchmarks
⏩ 1522 skipped benchmarks¹

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

	Mode	Benchmark	`BASE`	`HEAD`	Efficiency
❌	Simulation	`bitwise_not_vortex_buffer_mut[1024]`	477.2 ns	535.6 ns	-10.89%
❌	Simulation	`bitwise_not_vortex_buffer_mut[128]`	317.8 ns	376.1 ns	-15.51%
❌	Simulation	`map_each[BufferMut<i32>, 128]`	770.6 ns	858.1 ns	-10.2%

_{Comparing myrrc/primitive-ffi (a3c15ad) with develop (0ea8973)}

1522 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. ↩