Extend ImageLoader to be able to load images at a given height and width

[arunjose696]

Extend ImageLoader to able to load images at a given target height and width in addition to the current behavior of only being able to load images at a target zoom. This is required to load images in svg format at custom height and width.

The extensions added in this change is used in #2526 That PR also contains snippets through which these changes are tested.

This depends on #2514, Only last commit is relevant for this PR

[github-actions]

Test Results

  118 files  ±0    118 suites  ±0   10m 21s ⏱️ +5s
4 440 tests ±0  4 418 ✅  - 2  17 💤 ±0  5 ❌ +2 
  298 runs  ±0    289 ✅  - 2   4 💤 ±0  5 ❌ +2 

For more details on these failures, see this check.

Results for commit 920ecbb. ± Comparison against base commit 810cbcc.

♻️ This comment has been updated with latest results.

[HeikoKlare]

Overall, this change looks good to me. I am just wondering if the term "target" in all the methods/variables is appropriate and helpful. In the zoom case, we have the distinction between fileZoom and targetZoom as we need to know which zoom an image represents. But for the size case there is no such distinction, as you just need to tell the size you want to have. So I think we should maybe remove all the "target" and just call everything width, height, loadBySize etc.

[arunjose696]

Overall, this change looks good to me. I am just wondering if the term "target" in all the methods/variables is appropriate and helpful. In the zoom case, we have the distinction between fileZoom and targetZoom as we need to know which zoom an image represents. But for the size case there is no such distinction, as you just need to tell the size you want to have. So I think we should maybe remove all the "target" and just call everything width, height, loadBySize etc.

Done

[HeikoKlare]

I fixed a typo in the commit message and added @Michael5601 as co author as the code for the initial prototype was developed by him: Michael5601#2

[Michael5601]

Thank you for finishing the prototype. It's very nice to see all the work getting merged now :).
And thank you @HeikoKlare for remembering to mention my name on the changes.