perf[vortex-array]: don't materialize const arrays in to_arrow_dictionary #6265

Performance Regression: -32.7%

❌ 1 regressed benchmark
✅ 1137 untouched benchmarks
⏩ 1265 skipped benchmarks¹

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

	Mode	Benchmark	`BASE`	`HEAD`	Efficiency
❌	Simulation	`chunked_bool_into_canonical[(1000, 10)]`	43 µs	63.9 µs	-32.7%

_{Comparing asubiotto/constantdict (00403b6) with develop (0d0fc63)}

1265 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. ↩