cleanup(storage)!: rename download_resume_policy

[coryan]

And the related types, updated all the documentation and comments to use
read instead of download.

Fixes #2888

[codecov]

Codecov Report

❌ Patch coverage is 91.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 94.86%. Comparing base (a1b3758) to head (3d84efa).
⚠️ Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
src/storage/src/storage/read_object.rs	88.88%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2903   +/-   ##
=======================================
  Coverage   94.86%   94.86%           
=======================================
  Files         104      104           
  Lines        4339     4339           
=======================================
  Hits         4116     4116           
  Misses        223      223           

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