[Feature] Same model with texture variations

[Mirazez]

🐞 Feature Description

Add a support for changing texture of all bones, which it use (now it need to fully clone model and change texture - it takes up a lot of memory in resourcepack). I think it will works in resource pack with parent model and models, where will change just a texture.

🧪 Example / Mock-up (Optional)

For getting an unique id (like group) for changable texture - make name of textures like
Changable:

  first:koenigsegg_agera_r_white // Can change with 'koenigsegg_agera_r_red'
  first:koenigsegg_agera_r_red // Can change with 'koenigsegg_agera_r_white'
  unique_texture_what_does_not_change // Static texture

As a default changable texture will take a first texture in group

Of course it need to make integration in api for TrackerUpdateAction and MythicMobs

  tracker.update(
    TrackerUpdateAction.changeDynamicTexture("first", "koegnisegg_agera_r_red"),
    BonePredicate.TRUE
  )

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🌍 Environment (Optional but Helpful)

• Server software & version: Folia 1.21.8
• BetterModel version: 2.0.0
• Java version: 1.21.8

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Disclaimer

The following environments are not supported, and feature requests relying on these conditions will not be considered:

- Informal / modified launchers (e.g., Feather Client)
- Closed-source mods/plugins (Optifine, ItemsAdder, Nexo, etc.)
- Hybrid server platforms (e.g., Arclight)
- Legacy server versions (1.21.1 or lower)
- Bedrock Edition
- Extremely outdated CPU / hardware
- Features fundamentally **impossible on server-side** due to engine or protocol limitations