docs: clarify client URL example wording in README

The sentence pointed at a localhost URL and called it a "remote server",
which reads oddly since nothing earlier in the README starts a server on
that port. Present the URL as an example and describe what actually
changes: the same client code talks to a server over HTTP.

Closes #3313

No-Verification-Needed: doc-only wording change in README.md

Author: maxisbey

README.md

@@ -105,7 +105,7 @@ async def main() -> None:
 asyncio.run(main())
 ```
 
-Swap `mcp` for `"http://localhost:8000/mcp"` and the exact same code talks to a remote server.
+Swap `mcp` for a URL like `"http://localhost:8000/mcp"` and the exact same code talks to a server over HTTP.
 
 ## Contributing