feat(dispatcher): constrained global arguments

[lengau]

Fixes #219

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[codecov]

Codecov Report

Attention: Patch coverage is 97.72727% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 94.85%. Comparing base (99394c9) to head (8316c77).
Report is 7 commits behind head on main.

❗ Current head 8316c77 differs from pull request most recent head ca5e5c3. Consider uploading reports for the commit ca5e5c3 to get more accurate results

Files	Patch %	Lines
craft_cli/dispatcher.py	97.29%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #220      +/-   ##
==========================================
+ Coverage   93.24%   94.85%   +1.61%     
==========================================
  Files           7        8       +1     
  Lines        1080     1107      +27     
  Branches      200      211      +11     
==========================================
+ Hits         1007     1050      +43     
+ Misses         66       53      -13     
+ Partials        7        4       -3     

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[cmatsuoka]

choices also exists in argparse, will validator and case_sensitive options increase the gap between global argument handling and command-specific argument handling instead of reducing it? Ideally we should have an uniform way to handle all arguments.

[lengau]

validator is equivalent to argparse's type - I can rename if you'd like.

case_sensitive is different, but is there for backwards compatibility in the way we handle --verbosity, which was previously case-insensitive due to special handling. Looking over it again, I wonder if I could just run the validator before limiting choices and make a special verbosity_validator function that returns the correct emitter mode.