feat: enhance type conversion fallback in validators

[almas-x]

When JSON request bodies are decoded into map[string]interface{} numeric fields become float64. The enum/in validation only handled string, int and uint types, causing valid JSON numbers to fail validation unless callers explicitly converted them with Filters. This change keeps the existing convToBasicType attempt and, if that fails, falls back to converting the value to a string and re-using the same enum matching logic. It's a small, backward-compatible fix that lets in: rules work with numbers coming from JSON without requiring extra Filters.

This update addresses goravel/goravel#816