ENH: Add type annotation information

[jhlegarreta]

Add type annotation information: add the py.typed file.

Documentation:
https://typing.readthedocs.io/en/latest/spec/distributing.html#packaging-typed-libraries

[jhlegarreta]

@effigies as I did not see this in NiBabel wondering whether it is strictly necessary:
https://github.com/nipreps/nifreeze/pull/31/files#diff-50c86b7ed8ac2cf95bd48334961bf0530cdc77b5a56f852c5c61b89d735fd711R126

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 65.84%. Comparing base (6b6ba70) to head (4644fd0).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #31   +/-   ##
=======================================
  Coverage   65.84%   65.84%           
=======================================
  Files          18       18           
  Lines         931      931           
  Branches      119      119           
=======================================
  Hits          613      613           
  Misses        274      274           
  Partials       44       44           

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[effigies]

File should go inside src/nifreeze, not src/. We use hatchling, so there's no need to configure setuptools. I don't think you'll need to do anything else but move the py.typed file.

[jhlegarreta]

File should go inside src/nifreeze, not src/. We use hatchling, so there's no need to configure setuptools. I don't think you'll need to do anything else but move the py.typed file.

Done.

[effigies]

Looks good:

󰅂 unzip -l dist/*.whl | grep -v .py$
     1:	Archive:  dist/nifreeze-25.0.0.dev9-py3-none-any.whl
     2:	  Length      Date    Time    Name
     3:	---------  ---------- -----   ----
    10:	        0  02-02-2020 00:00   nifreeze/py.typed
    30:	      941  02-02-2020 00:00   nifreeze/registration/config/b0-to-b0_level0.json
    31:	      895  02-02-2020 00:00   nifreeze/registration/config/dwi-to-b0_level0.json
    32:	      877  02-02-2020 00:00   nifreeze/registration/config/dwi-to-dwi_level0.json
    33:	      861  02-02-2020 00:00   nifreeze/registration/config/dwi-to-dwi_level1.json
    38:	     9171  02-02-2020 00:00   nifreeze-25.0.0.dev9.dist-info/METADATA
    39:	       87  02-02-2020 00:00   nifreeze-25.0.0.dev9.dist-info/WHEEL
    40:	       51  02-02-2020 00:00   nifreeze-25.0.0.dev9.dist-info/entry_points.txt
    41:	    10141  02-02-2020 00:00   nifreeze-25.0.0.dev9.dist-info/licenses/LICENSE
    42:	      240  02-02-2020 00:00   nifreeze-25.0.0.dev9.dist-info/licenses/NOTICE
    43:	     3351  02-02-2020 00:00   nifreeze-25.0.0.dev9.dist-info/RECORD
    44:	---------                     -------
    45:	   171957                     40 files