feat(mapper): support contextual serializers and casters

[innocenzi]

Depends on #1789
Closes #1522

This pull requests adds the concept of contexts to casters and serializers. It works by adding the ability to the mapper to use a context (string, enum or Context class that might hold data).

The mapper will inject the context to serializers/casters/mappers when resolved from the container, and will use serializers/casters registered for that context (or fall back to the default context).

This allows, for instance, the database to use dedicated serializers/casters. Before this pull request, we had to manually add a condition for boolean values to be transformed properly depending on the current database dialect. After this PR, this functionality works through a serializer:

#[Context(DatabaseContext::class)]
final class BooleanSerializer implements Serializer
{
    public function __construct(
        private DatabaseContext $context,
    ) {}

    public static function for(): array
    {
        return ['bool', 'boolean'];
    }

    public function serialize(mixed $input): string
    {
        if (! is_bool($input)) {
            throw new ValueCouldNotBeSerialized('boolean');
        }

        return match ($this->context->dialect) {
            DatabaseDialect::POSTGRESQL => $input ? 'true' : 'false',
            default => $input ? '1' : '0',
        };
    }
}

Serializers and casters are now discovered by Discovery instead of being registered through an initializer. Since ordering is important for them, they support priority ordering through Tempest\Core\Priority.

It's also possible for userland to register their own casters and serializers this way. To use a specific context, we use the in method on ObjectFactory (or SerializerFactory or CasterFactory):

$array = map($object)
    ->in('inertia')
    ->toArray();

To pass data to a caster/serializer/mapper, an object extending Context may be used instead of a string/enum. The database package now uses a DatabaseContext under the hood:

return map($query->fetch())
    ->with(SelectModelMapper::class)
    ->in(new DatabaseContext(dialect: $this->dialect))
    ->to($this->model->getName());

As seen above, the BooleanSerializer expects a DatabaseContext in its constructor. Note that for now, the injection works by parameter name, not parameter type.

[innocenzi]

This is ready for an initial review! What do we think about this approach?

[innocenzi]

@brendt ready for another review!