Allowing endpoints that don't end in '/'

[glecaros]

This pull request makes significant changes to the AIChatProtocolClient class in the sdk/js/packages/client/src/client.ts file. The changes primarily focus on the way URLs are handled within the client. A new function splitURL is introduced to parse the URL into origin and path components. The AIChatProtocolClient constructor and methods are then updated to use these separate components instead of the absolute URL.

URL Handling Changes:

• sdk/js/packages/client/src/client.ts: Introduced a new function splitURL which takes a URL string as input and returns a tuple containing the origin and path.
• sdk/js/packages/client/src/client.ts: Updated the AIChatProtocolClient constructor to use the splitURL function to parse the endpoint into origin and path. The path is stored in a new basePath member variable. The getClient function is then called with the origin instead of the absolute endpoint.
• sdk/js/packages/client/src/client.ts: Updated the post method call in the client.path function to use this.basePath instead of the root path ("/").
• sdk/js/packages/client/src/client.ts: Similarly, updated the post method call in the client.path function within the asStream function to use this.basePath instead of the root path ("/stream").