ORM Bugs

[JohananOppongAmoateng]

This PR addresses multiple issues to improve django-polymorphic's reliability and usability.

Saving polymorphic objects from one database to another caused ForeignKeyViolation because polymorphic_ctype_id referenced ContentType IDs from the source database.

Database routers weren't respected - ContentType was always fetched from default database even when routers specified a different database.

Closes #486
Closes #446

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.39%. Comparing base (9f5e0fc) to head (a667f57).
⚠️ Report is 12 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #757      +/-   ##
==========================================
+ Coverage   78.28%   78.39%   +0.10%     
==========================================
  Files          26       26              
  Lines        1543     1569      +26     
  Branches      244      248       +4     
==========================================
+ Hits         1208     1230      +22     
- Misses        260      263       +3     
- Partials       75       76       +1     

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[bckohan]

Great work @JohananOppongAmoateng

I'd like to keep PRs logically homogenous. Could you please separate out the fix for #505 into a separate PR? It is unrelated to the db routing issues (which I want to accept as is). I'm not sure about supporting 505 yet or not.

[JohananOppongAmoateng]

Great work @JohananOppongAmoateng

I'd like to keep PRs logically homogenous. Could you please separate out the fix for #505 into a separate PR? It is unrelated to the db routing issues (which I want to accept as is). I'm not sure about supporting 505 yet or not.

@bckohan your requested changes have been done

[bckohan]

Great thanks!