feature: Support OpenAPI URL Synchronization for API Import

Currently, the API import feature only supports file upload. I would like to propose adding support for importing APIs through OpenAPI URL synchronization.

This would allow users to:

1. Add their local Swagger JSON URL directly to the system

2. Use a sync button to import new APIs whenever the source API documentation is updated

3. Maintain a real-time connection between the source OpenAPI documentation and the imported APIs

Benefits:

• Streamlines the API import process

• Reduces manual work for keeping APIs up-to-date

• Ensures API documentation stays synchronized with the source

• Particularly useful for developers working with local Swagger instances

Proposed Implementation: Add an alternative import method that allows users to:

1. Input an OpenAPI/Swagger URL

2. Validate the URL and fetch initial API documentation

3. Provide a sync button to refresh/update the APIs when needed