Feat: enforce compile-time model-safe query predicates

[VoidClancy]

1- Define PredicateOf[M] interface instead of Predicate, with a phantom(M) method to differentiate between models at compile-time

2- Define Predicate[M] and UniquePredicate[M] structs that house predicate data and implement PredicateOf[M]

3- Adapt Field[M, T], UniqueField[M, T], StringField[M], and StringUniqueField[M] to be parameterized by model type M, ensuring returned predicates are model-specific

4- Refactor logical operator helpers And[M], Or[M], and Not[M] to be generic over the model type parameter

5- Parameterize QueryParams[M] and update FindUniqueBuilder, FindFirstBuilder, and FindManyBuilder to accept model-scoped predicates

6- Update relation query generation helpers and loaders to work with the generic QueryParams[M] container