Migrate to pydantic v2

[amrit110]

PR Type ([Feature | Fix | Documentation | Test])

Update

Short Description

• Migrate to pydanticv2 which has improved features and functionality

Tests Added

...

[amrit110]

Closing as superseded by #769, which completes this migration properly: this PR's @model_validator(skip_on_failure=True) isn't valid pydantic v2 syntax (that parameter belongs to v1's root_validator), and it never touched report.py's .dict()/.json()/.validate() calls or the Extra/Config class pattern used throughout the model-card system. #769 migrates all of cyclops/report (and deploy/report/api) to pydantic v2 idioms with the full test suite passing.