📝 Add proxyUrl option documentation

[amortemousque]

Motivation

Add proxy URL README documentation

Changes

Update docs

Testing

Locally

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I have gone over the contributing documentation.

[codecov-commenter]

Codecov Report

Merging #1050 (92266ba) into main (356c5a4) will decrease coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1050      +/-   ##
==========================================
- Coverage   89.01%   88.99%   -0.03%     
==========================================
  Files          87       87              
  Lines        4134     4134              
  Branches      950      950              
==========================================
- Hits         3680     3679       -1     
- Misses        454      455       +1     

Impacted Files	Coverage Δ
packages/core/src/tools/timeUtils.ts	90.90% <0.00%> (-3.04%)	⬇️

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