feat: bounded size auto sharding via zarr.config

[ilan-gold]

closes #3568

TODO:

• Add unit tests and/or doctests in docstrings
• Add docstrings and API docs for any new/modified user-facing classes and functions
• New/modified features documented in docs/user-guide/*.md
• Changes documented as a new file in changes/
• GitHub Actions have all passed
• Test coverage is 100% (Codecov passes)

[codecov]

Codecov Report

❌ Patch coverage is 86.66667% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 61.90%. Comparing base (d0c3b7f) to head (d72419f).

Files with missing lines	Patch %	Lines
src/zarr/core/chunk_grids.py	86.66%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3574      +/-   ##
==========================================
+ Coverage   61.87%   61.90%   +0.03%     
==========================================
  Files          85       85              
  Lines       10134    10147      +13     
==========================================
+ Hits         6270     6282      +12     
- Misses       3864     3865       +1     

Files with missing lines	Coverage Δ
src/zarr/core/config.py	38.88% <ø> (ø)
src/zarr/core/chunk_grids.py	63.33% <86.66%> (+3.52%)	⬆️

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[ilan-gold]

Not sure I fully grasp what is going on with codecov, it looks like the tests run and assert the things they should and use the funcionality promised.