fix(parser): type hints should reflect primitive types support

[catarinacps]

Issue number: closes #8174

Summary

As per #4502, primitive types are supported by the parser utility. However, the type hints utilized in the functions and envelopes there do not reflect that at the moment, making type checkers lack when inferring the return types, for example. This aims to improve this situation by adjusting the type hints there.

Changes

Please provide a summary of what's being changed

This PR thus changes the TypeVar used in the envelope types' functions to T, introduced in #4502. It also sets the BaseEnvelope parser(...) method with envelope overload return type hint to T | list[T | None] | None to allow those subclasses to overload the method correctly.

User experience

Please share what the user experience looks like before and after this change

Before:

After the change the type checker will be able to narrow the type to list[EUMMessage], as that is the actual return type that should be shown.

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[boring-cyborg]

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[leandrodamascena]

Oi @catarinacps, tudo bem? :D

This is a great contribution, clean and consistent. Swapping Model (bound to BaseModel) to unbound T across all envelopes finally makes type checkers aware of the primitive types support we added in #4502. Love it!

APROVADO!

[sonarqubecloud]

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 SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.72%. Comparing base (2e11129) to head (1b5d045).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8175   +/-   ##
========================================
  Coverage    96.72%   96.72%           
========================================
  Files          286      286           
  Lines        14341    14341           
  Branches      1200     1200           
========================================
  Hits         13871    13871           
  Misses         341      341           
  Partials       129      129           

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[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!