core: improve storage mgmt

[dominic-r]

Closes AUTH-X
Closes QA-1
Closes #11939
Closes #13463
Closes #11964
Closes #12985
Closes #11176

Todo

• Default application icon if load error instead of "Application"
• Make all tests pass
• Test with brands
• Test with filesystem
• Fix UI Feedback on app creation err for media for example
• Get the right S3 presigned params (if it even matters)
• QA

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[codecov]

Codecov Report

Attention: Patch coverage is 15.68228% with 828 lines in your changes missing coverage. Please review.

Project coverage is 83.46%. Comparing base (4e4adcc) to head (199dfb0).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
authentik/root/tests/test_storages.py	15.78%	400 Missing ⚠️
authentik/root/storages.py	13.38%	369 Missing ⚠️
authentik/core/tests/test_applications_api.py	20.00%	28 Missing ⚠️
authentik/lib/utils/file.py	15.38%	22 Missing ⚠️
authentik/core/models.py	0.00%	4 Missing ⚠️
authentik/core/api/applications.py	50.00%	2 Missing ⚠️
authentik/root/settings.py	33.33%	2 Missing ⚠️
authentik/api/tests/test_schema.py	85.71%	1 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (4e4adcc) and HEAD (199dfb0). Click for more details.

HEAD has 2 uploads less than BASE

Flag	BASE (4e4adcc)	HEAD (199dfb0)
unit	10	8

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #13406      +/-   ##
==========================================
- Coverage   92.73%   83.46%   -9.28%     
==========================================
  Files         794      795       +1     
  Lines       40430    41332     +902     
==========================================
- Hits        37492    34496    -2996     
- Misses       2938     6836    +3898     

Flag	Coverage Δ
e2e	47.49% <1.77%> (-0.53%)	⬇️
integration	24.06% <1.77%> (-0.25%)	⬇️
unit	81.00% <15.68%> (-9.51%)	⬇️

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[dominic-r]

Ok, ive got a decent working version. Still some things to iron out, tho. I'll make this as ready for review to get a few suggestions/comments