[Enhancement] Support real-time skin replacement mods/plugins for webhook avatars

[Miamlya]

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Description

Fabric tailor mod support for skin avatars integration

[Xujiayao]

Also SkinsRestorer

[Xujiayao]

Please use the latest build.

Support Geyser and all real-time skin replacement mods/plugins.

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The new default value of avatarApi is this:

"avatarApi": "https://mc-heads.net/avatar/{player_uuid}.png",

If you want it to support real-time skin replacement mods/plugins or Geyser, you should change its value to the following:

"avatarApi": "https://mc-heads.net/avatar/{player_textures}.png",

I may change the default to {player_textures} before releasing the new version, or even consider rename avatarApi to avatar_url.