Add widget to apply transform and produce new layer

[andreasmarnold]

Work in progress to apply affine transformation to another layer. Still need to add tests but it seems to be working.

[codecov-commenter]

Codecov Report

Merging #78 (e1a4cf5) into main (e373c44) will increase coverage by 2.47%. The diff coverage is 100.00%.

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@@            Coverage Diff             @@
##             main      #78      +/-   ##
==========================================
+ Coverage   86.95%   89.42%   +2.47%     
==========================================
  Files           5        6       +1     
  Lines         184      227      +43     
==========================================
+ Hits          160      203      +43     
  Misses         24       24              

Files	Coverage Δ
src/affinder/__init__.py	71.42% <100.00%> (+4.76%)	:arrow_up:
src/affinder/_tests/test_affinder.py	100.00% <100.00%> (ø)
src/affinder/apply_tf.py	100.00% <100.00%> (ø)

[jni]

@andreasmarnold I've made a few changes, you can have a look at the commits above for context. 😊 (btw: by default, when you use a branch in your own fork to make a PR to an upstream repo, the owners of that repo (🙋‍♂️) can push to that specific branch, which is what I did here.)

But anyway, now locally you can grab these changes with git switch main; git pull upstream main, and we can move on to the next thing! 😊