add MMOItems support

[1robie]

This pull request adds support for the MMOItems plugin integration. The main changes include introducing a new MMOItemsLoader class for loading MMOItems materials, updating dependency management, and ensuring the plugin recognizes MMOItems as an optional dependency.

MMOItems integration:

• Added new class MMOItemsLoader in Hooks/MMOItems/src/main/java/fr/maxlego08/menu/hooks/mmoitems/MMOItemsLoader.java to handle loading MMOItems items via the API.
• Registered MMOItemsLoader in the main plugin initialization (ZMenuPlugin.java) so it is used when MMOItems is active.

Dependency and build configuration:

• Created a new Gradle build configuration for the MMOItems hook in Hooks/MMOItems/build.gradle.kts, including the MMOItems API as a compile-only dependency.
• Included Hooks:MMOItems in the Gradle settings to ensure the module is built.

Plugin system updates:

• Added MMOITEMS to the Plugins enum so it can be recognized and activated.
• Declared MMOItems as a softdepend in plugin.yml to indicate optional support.