feat: Add registration metadata to boldref-to-anat transforms

[effigies]

Closes #3496.

[codecov]

Codecov Report

❌ Patch coverage is 88.88889% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.56%. Comparing base (c961b3c) to head (3ea4c4c).
⚠️ Report is 195 commits behind head on master.

Files with missing lines	Patch %	Lines
fmriprep/workflows/bold/registration.py	88.88%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3500      +/-   ##
==========================================
+ Coverage   73.50%   73.56%   +0.06%     
==========================================
  Files          60       60              
  Lines        4582     4600      +18     
  Branches      585      585              
==========================================
+ Hits         3368     3384      +16     
- Misses       1085     1087       +2     
  Partials      129      129              

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[effigies]

https://output.circle-artifacts.com/output/job/6c4e4e34-c826-457a-9d1f-11cdf635de1e/artifacts/0/tmp/ds054/fmriprep/sub-100185/func/sub-100185_task-machinegame_run-01_from-boldref_to-T1w_mode-image_desc-coreg_xfm.json:

{
  "GeneratedBy": [
    {
      "Name": "mri_coreg",
      "Version": "7.3.2"
    }
  ],
  "Sources": [
    "bids::sub-100185/func/sub-100185_task-machinegame_run-01_desc-coreg_boldref.nii.gz"
  ]
}

https://output.circle-artifacts.com/output/job/955df01f-5407-454f-899b-3d65cd9c1aff/artifacts/0/tmp/ds210/fmriprep/sub-02/func/sub-02_task-cuedSGT_run-01_from-boldref_to-T1w_mode-image_desc-coreg_xfm.json:

{
  "GeneratedBy": [
    {
      "Name": "mri_coreg",
      "Version": "7.3.2"
    }
  ],
  "Sources": [
    "bids::sub-02/func/sub-02_task-cuedSGT_run-01_desc-coreg_boldref.nii.gz"
  ]
}

https://output.circle-artifacts.com/output/job/95d2b2bf-3ffc-4bc1-a46b-8f9a4861d325/artifacts/0/full-run/sub-01/func/sub-01_task-mixedgamblestask_run-01_from-boldref_to-T1w_mode-image_desc-coreg_xfm.json:

{
  "FinalCost": 0.649006,
  "GeneratedBy": [
    {
      "Name": "bbregister",
      "Version": "7.3.2"
    }
  ],
  "Sources": [
    "bids::sub-01/func/sub-01_task-mixedgamblestask_run-01_desc-coreg_boldref.nii.gz"
  ]
}

[mgxd]

forgot to finalize this