refactor: pull minmax logic off main window, and reduce minmax widget layout logic

[tlambert03]

puts the logic for updating minmax on the minmax widget itself, removing it from the main window. Also simplifies the layout down to a couple lines

[codecov]

Codecov Report

Base: 85.26% // Head: 84.98% // Decreases project coverage by -0.28% ⚠️

Coverage data is based on head (8ae593e) compared to base (b6922ab).
Patch coverage: 92.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #233      +/-   ##
==========================================
- Coverage   85.26%   84.98%   -0.29%     
==========================================
  Files          14       14              
  Lines         991      979      -12     
==========================================
- Hits          845      832      -13     
- Misses        146      147       +1     

Impacted Files	Coverage Δ
...apari_micromanager/_gui_objects/_min_max_widget.py	90.90% <90.90%> (-9.10%)	⬇️
src/napari_micromanager/main_window.py	94.28% <100.00%> (+0.45%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.