Support casting to Decimal in Primitive CastKernel

[mhk197]

Add casts from integer primitive arrays to decimal arrays.

[codspeed-hq]

Merging this PR will degrade performance by 35.45%

❌ 1 regressed benchmark
✅ 1940 untouched benchmarks
🆕 3 new benchmarks
⏩ 85 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	cast_i32_to_u32[65536]	1.8 ms	2.8 ms	-35.45%
🆕	Simulation	cast_i64_to_decimal38_scale2[65536]	N/A	3.7 ms	N/A
🆕	Simulation	cast_i32_to_decimal9_scale2[65536]	N/A	1.4 ms	N/A
🆕	Simulation	cast_i32_to_decimal9_scale0[65536]	N/A	746.8 µs	N/A

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 mk/primitive-to-decimal-cast (cc85221) with develop (329bba2)}

Footnotes

1. 85 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. ↩