Refact: switch from google-generativeai to google-genai

[Magicbook1108]

What problem does this PR solve?

Refact: switch from oogle-generativeai to google-genai #13132
Refact: commnet out unused pywencai.

Type of change

• Refactoring

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 33.21%. Comparing base (1094416) to head (dc996ff).
⚠️ Report is 17 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #13140       +/-   ##
===========================================
- Coverage   44.05%   33.21%   -10.84%     
===========================================
  Files          43       43               
  Lines        9415     9501       +86     
  Branches      107      107               
===========================================
- Hits         4148     3156      -992     
- Misses       5248     6326     +1078     
  Partials       19       19               

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