Add partial encoding support (sync only)

[LDeakin]

This is mainly to support incremental writing of large shards similar to the encoding procedure outlined in the sharding specification.

Addresses LDeakin/zarrs_tools#9.

[codecov]

Codecov Report

Attention: Patch coverage is 40.61662% with 443 lines in your changes missing coverage. Please review.

Project coverage is 82.03%. Comparing base (952f543) to head (8277daf).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ay/codec/array_to_array_partial_encoder_default.rs	0.00%	72 Missing ⚠️
...s/src/array/codec/array_partial_encoder_default.rs	0.00%	59 Missing ⚠️
...s/src/array/codec/bytes_partial_encoder_default.rs	0.00%	49 Missing ⚠️
...arrs/src/array/codec/array_to_bytes/codec_chain.rs	38.59%	35 Missing ⚠️
...rray_to_bytes/sharding/sharding_partial_encoder.rs	90.90%	18 Missing ⚠️
...ay/codec/array_to_array/bitround/bitround_codec.rs	0.00%	14 Missing ⚠️
.../codec/array_to_array/transpose/transpose_codec.rs	0.00%	14 Missing ⚠️
...rc/array/codec/array_to_bytes/bytes/bytes_codec.rs	0.00%	14 Missing ⚠️
.../array/codec/array_to_bytes/pcodec/pcodec_codec.rs	0.00%	14 Missing ⚠️
.../src/array/codec/array_to_bytes/vlen/vlen_codec.rs	0.00%	14 Missing ⚠️
... and 11 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #45      +/-   ##
==========================================
- Coverage   83.10%   82.03%   -1.07%     
==========================================
  Files         162      166       +4     
  Lines       22532    23259     +727     
==========================================
+ Hits        18725    19081     +356     
- Misses       3807     4178     +371     

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