Add data quality control functionality

[juaristi22]

From Nikhil's example:

" If validation fails, you get useful error messages explaining exactly what's wrong.
For example, a person DataFrame in the UK might require columns like person_id, age, employment_income, and hours_worked. The validation would ensure person_id is unique, age is a positive integer, employment_income is non-negative, and hours_worked falls within reasonable bounds. This catches data quality issues early, before they can affect simulation results."

Some of this functionality may be county-specific and some may be agnostic.