feat: `configFile: false` to disable config file loading

[kricsleo]

trafficstars

resolves #236

This PR brings back support for configFile: false.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 61.70213% with 18 lines in your changes missing coverage. Please review.

Project coverage is 77.79%. Comparing base (42d9697) to head (689ce39). Report is 131 commits behind head on main.

Files with missing lines	Patch %	Lines
src/watch.ts	0.00%	11 Missing :warning:
src/loader.ts	80.55%	7 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #245      +/-   ##
==========================================
+ Coverage   76.92%   77.79%   +0.87%     
==========================================
  Files           7        6       -1     
  Lines         806      635     -171     
  Branches       80      124      +44     
==========================================
- Hits          620      494     -126     
+ Misses        184      141      -43     
+ Partials        2        0       -2     

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[pi0]

Thanks for the time on this PR.

PR looks nice, but I'm a little bit hesitant if it adds real value vs internal complexity.

[kricsleo]

if it adds real value vs internal complexity.

Reasonable concern. We can just hold off on it until more users/real cases require this. ❤️