REF: Extract shared functionality into common

[jerdra]

1. 15c1355 - move make_3d_from_4d into niviz.common.image
2. 1e09a85 - update volume interface to match move
3. ae3c5ca - move niviz.surface into niviz.common.surface, adjust niviz.interfaces.surface as well
4. fd2c78b - add annotation import

[codecov]

Codecov Report

Merging #17 (fd2c78b) into main (b428311) will decrease coverage by 2.15%.
The diff coverage is 17.14%.

❗ Current head fd2c78b differs from pull request most recent head 539cb76. Consider uploading reports for the commit 539cb76 to get more accurate results

@@            Coverage Diff             @@
##             main      #17      +/-   ##
==========================================
- Coverage   59.69%   57.54%   -2.16%     
==========================================
  Files          13       15       +2     
  Lines         980     1034      +54     
==========================================
+ Hits          585      595      +10     
- Misses        395      439      +44     

Flag	Coverage Δ
unittests	57.54% <17.14%> (-2.16%)	⬇️

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Impacted Files	Coverage Δ
niviz/common/surface.py	12.24% <12.24%> (ø)
niviz/interfaces/surface.py	36.30% <12.50%> (ø)
niviz/interfaces/volume.py	69.66% <20.00%> (+2.27%)	⬆️
niviz/common/image.py	50.00% <50.00%> (ø)

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