feat: support creating tickets directly in Zammad

[nijel]

Proposed changes

• drops CSP exceptions on management page
• nicer integration on management page
• opt-in integration for concact and hosting forms

Checklist

• Lint and unit tests pass locally with my changes.
• I have added tests that prove my fix is effective or that my feature works.
• I have added documentation to describe my feature.
• I have squashed my commits into logic units.
• I have described the changes in the commit messages.

Other information

[codecov]

Codecov Report

Attention: Patch coverage is 70.09346% with 32 lines in your changes missing coverage. Please review.

Project coverage is 90.93%. Comparing base (fead975) to head (6d01cc0).
Report is 43 commits behind head on main.

Files with missing lines	Patch %	Lines
weblate/wladmin/views.py	39.13%	13 Missing and 1 partial ⚠️
weblate/utils/zammad.py	74.35%	8 Missing and 2 partials ⚠️
weblate/accounts/views.py	55.55%	6 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #13152      +/-   ##
==========================================
- Coverage   90.96%   90.93%   -0.04%     
==========================================
  Files         599      601       +2     
  Lines       62060    62148      +88     
  Branches     6397     6404       +7     
==========================================
+ Hits        56454    56512      +58     
- Misses       3949     3975      +26     
- Partials     1657     1661       +4     

Files with missing lines	Coverage Δ
weblate/billing/views.py	75.32% <ø> (ø)
weblate/middleware.py	82.66% <ø> (-0.48%)	⬇️
weblate/urls.py	82.50% <ø> (ø)
weblate/utils/models.py	100.00% <100.00%> (ø)
weblate/utils/tests/test_zammad.py	100.00% <100.00%> (ø)
weblate/accounts/views.py	83.81% <55.55%> (-0.51%)	⬇️
weblate/utils/zammad.py	74.35% <74.35%> (ø)
weblate/wladmin/views.py	67.69% <39.13%> (-2.38%)	⬇️