More CI updates

[EmmEff]

• Bump golangci-lint to v2.0.1
• Resolve issues discovered by same

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 47.41%. Comparing base (f1327e4) to head (01cb74f).

Files with missing lines	Patch %	Lines
internal/app/buildclient/build.go	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #291      +/-   ##
==========================================
- Coverage   47.48%   47.41%   -0.08%     
==========================================
  Files          19       19              
  Lines        1312     1314       +2     
==========================================
  Hits          623      623              
- Misses        621      623       +2     
  Partials       68       68              

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