MultiscaleImage handling

[Sonja-Stockhaus]

The user can either select a scale or the multi-scale images to be rendered are rasterized before

@timtreis, 2023-10-16: "Please also provide the first (pre-datashader) version of this notebook: scverse/spatialdata-notebooks#59 "

[codecov-commenter]

Codecov Report

Merging #164 (0fa93fa) into main (3e09dd1) will increase coverage by 0.86%.
The diff coverage is 89.07%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #164      +/-   ##
==========================================
+ Coverage   77.09%   77.95%   +0.86%     
==========================================
  Files          11       11              
  Lines        1196     1293      +97     
==========================================
+ Hits          922     1008      +86     
- Misses        274      285      +11     

Files	Coverage Δ
src/spatialdata_plot/pl/basic.py	87.68% <100.00%> (+1.80%)	⬆️
src/spatialdata_plot/pl/render.py	88.84% <100.00%> (+0.33%)	⬆️
src/spatialdata_plot/pl/render_params.py	100.00% <100.00%> (ø)
src/spatialdata_plot/pl/utils.py	62.52% <80.00%> (+2.65%)	⬆️

[timtreis]

• Cover usecase in which I plot a list of elements and pass a list to scale, elementwise matching
• Implement logic which decouples img-raster DPI from canvas size DPI as discussed

[LucaMarconato]

Just a quick comment, I have been using this new branch, works super smooth! Great work!