Add Swagger and relation splitting features

[omar-dulaimi]

Summary

• ✨ Add swagger flag to generate @ApiProperty decorators alongside class-validator decorators
• ✨ Add separateRelationFields flag to split models into base/relation classes for better NestJS integration
• 🔧 Support for all Prisma types including proper Float handling with @IsNumber
• 🧪 Comprehensive test coverage for both new features
• 📚 Updated documentation with examples and usage patterns
• ✅ Backward compatible - existing schemas work unchanged

Configuration Examples

Swagger Support

generator class_validator {
  provider = "prisma-class-validator-generator"
  swagger  = "true"
}

Relation Splitting

generator class_validator {
  provider               = "prisma-class-validator-generator"
  separateRelationFields = "true"
}

Full NestJS Integration

generator class_validator {
  provider               = "prisma-class-validator-generator"
  swagger                = "true"
  separateRelationFields = "true"
}

Test plan

• All existing tests pass (backward compatibility)
• New Swagger generation tests
• New relation splitting tests
• Documentation updated with examples
• Both flags work independently and together

Fixes #18