Create new branch for spine 4.0 version & update runtime

[johanzhu]

Description:

• This PR creates a separate branch to manage the Spine 4.0 runtime version.
• Updated the runtime to address some issues archived in Milestone 1.3: #88 #85 #66 #93 #94
• Merged SpineRenderer and SpineAnimation, and made SpineAnimation inherit from Renderer to streamline the API.

Detail change:

• example/main.ts : Update examples for new runtime api
• example/outline.ts: Fix some type script type error
• index.html: add upload dom element for local file upload example
• package.json: change package name
• rollup.config.js: Remove mini program support ( old mini program pack logic cause build error
• src/SpineAnimation.ts: Refract : Inherit from engine renderer，streamline spine api
• src/SpineRenderer.ts: remove
• src/core/MeshGenerator.ts: Support multi texture & Updated to adapt to the modifications in the renderer.
• src/core/SpineMesh.ts：Updated to adapt to the modifications in the renderer.
• src/index.ts：Update package exports
• src/loader/LoaderUtils.ts： Refract Loader , Consolidated core loading functions into loaderUtil.
• src/loader/SpineLoader.ts： Refract Loader to address issues
• src/spine-core/index.ts：Export all spine-core classes
• src/spine-core/polyfills.ts: Export module.

spine-core update：Updated spine-core, use npm module instead.