Simplify commands to automatically detect modality

[tsalo]

Closes #41.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 96.93252% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 70.35%. Comparing base (dd8cd8a) to head (9042f17).

Files with missing lines	Patch %	Lines
src/modelarrayio/cli/h5_to_mif.py	25.00%	3 Missing ⚠️
src/modelarrayio/cli/export_results.py	97.33%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #49      +/-   ##
==========================================
+ Coverage   69.10%   70.35%   +1.24%     
==========================================
  Files          17       19       +2     
  Lines        1162     1167       +5     
  Branches      211      228      +17     
==========================================
+ Hits          803      821      +18     
+ Misses        295      284      -11     
+ Partials       64       62       -2     

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[tien-tong]

Documentation:

• plot_voxel_workflow.py (line 125) still shows --output-ext, which no longer exists.
• plot_cifti_workflow.py (line 110) still shows --example-cifti, but the parser expects --example-file.
• outputs.rst (line 182) says MIF export writes .mif, but the code defaults to .mif.gz.

[tsalo]

@tien-tong I think I've address all of your comments. Would you mind taking another look?

[tien-tong]

LGTM!