feat: remove custom multipart parser

[hugomrdias]

Adds tests to store endpoint and improves upload tests with new mock for cluster

Tweak some types and deps to make ts happy

[cloudflare-workers-and-pages]

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[codecov-commenter]

Codecov Report

Merging #336 (2946367) into main (06ef32f) will not change coverage.
The diff coverage is n/a.

❗ Current head 2946367 differs from pull request most recent head 3cc2515. Consider uploading reports for the commit 3cc2515 to get more accurate results

@@            Coverage Diff            @@
##              main      #336   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files            5         5           
  Lines          786       786           
=========================================
  Hits           786       786           

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