refactor: Metadata handling

[provinzkraut]

Make the metadata extraction from type annotations more robust.

• Remove "duck typing" approach of extracting metadata from arbitrary types if they have attributes that match metadata attributes we're interested in
• Remove coupling to 3rd party libraries in core code (specifically Pydantic)
• Fully move metadata extraction responsibilities to plugins

---

Supersedes #3308.
Fixes #3710.
Fixes #3656.
Fixes #3722.

[provinzkraut]

@peterschutt If you have the time, a review or even a quick look from you would be greatly appreciated :)

[codecov]

Codecov Report

Attention: Patch coverage is 99.64413% with 1 line in your changes missing coverage. Please review.

Project coverage is 98.34%. Comparing base (d4e01f9) to head (34658d7).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
litestar/contrib/pydantic/utils.py	99.22%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3721      +/-   ##
==========================================
+ Coverage   98.29%   98.34%   +0.05%     
==========================================
  Files         330      331       +1     
  Lines       15139    15268     +129     
  Branches     2405     2443      +38     
==========================================
+ Hits        14881    15016     +135     
+ Misses        117      112       -5     
+ Partials      141      140       -1     

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[cofin]

I don't have anything to add other than nice work. It looks good to me.

[sonarqubecloud]

Quality Gate passed

Issues
3 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