fix: Add CORS Headers to HTTP error 500 responses

[MoritzWeber0]

Internal server error respones result in no CORS ALLOW_ORIGIN headers added to the response. This leads to wrong handling by the frontend. When there are no CORS headers, status code was 0, which was treated as "Backend not reachable".

There was already handling to add CORS headers, but it didn't add the ALLOW_ORIGIN header, which we add manually now.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 5 lines in your changes missing coverage. Please review.

Project coverage is 83.96%. Comparing base (5e66986) to head (04af21b).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
backend/capellacollab/__main__.py	0.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1843      +/-   ##
==========================================
- Coverage   84.01%   83.96%   -0.06%     
==========================================
  Files         194      194              
  Lines        6455     6459       +4     
  Branches      713      714       +1     
==========================================
  Hits         5423     5423              
- Misses        876      880       +4     
  Partials      156      156              

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[github-actions]

This report was generated by comparing c8d7993 with 5e66986.
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ArtifactName: reg

item	count
pass	287
change	1
new	0
delete	0

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Differences

Model Components_Model Sources_Git_Invalid URL_desktop.png

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