refactor: update Pydantic imports

[adhtruong]

Description

• Fixes issue described Significant performance drop when creating batch of pydantic models since pydantic 2.5.0 #576
• Tested with script

(polyfactory) ➜  polyfactory git:(perf-refactor-pydantic-imports) ✗ cat test.sh 
#!/usr/bin/env sh

.venv-fast/bin/python -m pip install -e . 
.venv-fast/bin/python -m pip install "pydantic<2.5.0"
.venv-slow/bin/python -m pip install -e . 
.venv-slow/bin/python -m pip install "pydantic==2.5.0"

.venv-slow/bin/python t.py
.venv-fast/bin/python t.py

with before and after this change

0.22203758300747722
0.1394521670008544
---
0.1482207500084769
0.13731049999478273

• Explanation here is pydantic now performs dynamic imports in some cases so affects performance when using attrs from the module. By importing directly for common attributes we avoid this cost.

Closes

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

Documentation preview will be available shortly at https://litestar-org.github.io/polyfactory-docs-preview/625

[cofin]

LGTM