feat: Add #[UseEloquentBuilder] attribute

[binaryfire]

This PR ports Laravel's #[UseEloquentBuilder] attribute to Hypervel, allowing models to declaratively specify a custom Eloquent builder class.

Summary

• Adds #[UseEloquentBuilder] attribute for declaring custom builder classes on models
• Modifies Model::newModelBuilder() to check for the attribute and use custom builders
• Adds resolveCustomBuilderClass() method with static caching for performance

Usage

use Hypervel\Database\Eloquent\Attributes\UseEloquentBuilder;
use Hypervel\Database\Eloquent\Model;

#[UseEloquentBuilder(UserBuilder::class)]
class User extends Model
{
    // ...
}

// Now User::query() returns a UserBuilder
$builder = User::query(); // instanceof UserBuilder

Changes

New Files

• src/core/src/Database/Eloquent/Attributes/UseEloquentBuilder.php - The attribute class
• tests/Core/Database/Eloquent/UseEloquentBuilderTest.php - Tests (8 tests, 13 assertions)

Modified Files

• src/core/src/Database/Eloquent/Model.php:
  • Added $resolvedBuilderClasses static cache
  • Modified newModelBuilder() to check for custom builder attribute
  • Added resolveCustomBuilderClass() method

How It Works

1. When newModelBuilder() is called on a model, it first checks the static cache
2. If not cached, resolveCustomBuilderClass() reads the #[UseEloquentBuilder] attribute via reflection
3. If a custom builder class is found and is a subclass of Builder, it's used
4. Otherwise, falls back to the default Hypervel\Database\Eloquent\Builder
5. Results are cached per model class to avoid repeated reflection calls

Notes

• PHP attributes are not inherited - child classes need their own #[UseEloquentBuilder] attribute if they want a custom builder
• This follows Laravel's implementation pattern