feat(cli): add mock s3 server

[melodicore]

Summary

A mock S3 server

[codecov]

Codecov Report

❌ Patch coverage is 45.00000% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 42.94%. Comparing base (7db864e) to head (2083821).
⚠️ Report is 40 commits behind head on main.

Files with missing lines	Patch %	Lines
...main/kotlin/elide/tool/cli/cmd/s3/ToolS3Command.kt	45.00%	8 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1753      +/-   ##
==========================================
+ Coverage   40.23%   42.94%   +2.71%     
==========================================
  Files         888      896       +8     
  Lines       37088    42435    +5347     
  Branches     5684     5962     +278     
==========================================
+ Hits        14922    18225    +3303     
- Misses      20229    22005    +1776     
- Partials     1937     2205     +268     

Flag	Coverage Δ
jvm	42.94% <45.00%> (+2.71%)	⬆️
lib	42.94% <45.00%> (+2.71%)	⬆️

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Files with missing lines	Coverage Δ
...ckages/cli/src/main/kotlin/elide/tool/cli/Elide.kt	33.17% <ø> (+0.02%)	⬆️
...main/kotlin/elide/tool/cli/cmd/s3/ToolS3Command.kt	45.00% <45.00%> (ø)

... and 574 files with indirect coverage changes

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