fix(storage)!: remove ChecksumEngine generic trait from the public API

[suzmue]

Remove the generic parameters for checksums from the public API. This does open the API to misuse a little easier, since we no longer can limit which setters for the checksum are enabled based on the type.

To simplify, remove the ChecksumEngine trait all together and create a new struct that holds a Crc32c and Md5 and let WriteObject and ReadObject do simple manipulations on them.

For #2896 , #2895

[codecov]

Codecov Report

❌ Patch coverage is 97.95918% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 96.70%. Comparing base (c9607c5) to head (0390253).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/storage/src/storage/write_object.rs	96.42%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2907      +/-   ##
==========================================
+ Coverage   96.19%   96.70%   +0.50%     
==========================================
  Files         105      105              
  Lines        4411     4365      -46     
==========================================
- Hits         4243     4221      -22     
+ Misses        168      144      -24     

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[coryan]

This will probably conflict with #2906 , but the fixes will be (I hope) easy

[dbolduc]

This is awesome! Thanks!

I just have an optional nit that could save some lines of code.

[suzmue]

@dbolduc I'll submit as is to make your work easier, and implement the nits in a follow up.