Support Variant arrays through DuckDB

[AdamGS]

Summary

This PR adds support for reading and writing ParquetVariant arrays in DuckDB. It surfaced some issues around session/write options wiring for non-default encodings, I'll take it out of this PR into a dedicated one as it seems like a general oversight?

[codspeed-hq]

Merging this PR will improve performance by 19.8%

⚠️ Unknown Walltime execution environment detected

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⚡ 1 improved benchmark
✅ 1250 untouched benchmarks

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	chunked_varbinview_opt_canonical_into[(1000, 10)]	225.2 µs	188 µs	+19.8%

Tip

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_{Comparing adamg/duckdb-variant-feature (75f7824) with develop (1a5079b)}