[Feature] Support drag-and-drop zip upload with multiple skills

[saynoword]

What is the feature you'd like to see?
Support uploading AI skills by dragging a zip file into the Nacos console, with the following capabilities:

1. Drag-and-drop zip upload: Allow users to drag a .zip file directly onto the Nacos console UI to upload AI skill resources.
2. Multi-skill zip support: A single zip package should be able to contain multiple skill definitions, which Nacos will parse and register individually.
   Why do you need this feature?
   Currently, uploading skills one by one is tedious and error-prone for users who manage multiple skills. Supporting batch upload via a zip package would:
   ● Improve user experience with drag-and-drop interaction
   ● Enable batch registration of multiple skills in one operation
   ● Simplify migration and sharing of skill sets between environments
   Suggested Solution
   ● Add drag-and-drop upload support in the console UI (console-ui module)
   ● Add a server-side API to accept zip file uploads, extract contents, validate skill definitions, and register them into the AI registry
   ● Define a standard zip structure, e.g.:
   skills.zip
   ├── skill-a/
   │ └── SKILL.md
   ├── skill-b/
   │ └── SKILL.md
   └── ...
   Environment
   ● Nacos version: 3.x (develop branch)
   ● Relevant modules: console-ui, ai, ai-registry-adaptor