Added warning regarding the uv command in the quickstart guide

Author: jerome3o-anthropic

quickstart/server.mdx

@@ -301,6 +301,10 @@ In this case, we'll add our single weather server like so:
 </Tab>
 </Tabs>
 
+<Warning>
+You may need to put the full path to the `uv` executable in the `command` field. You can get this by running `which uv` on MacOS/Linux or `where uv` on Windows.
+</Warning>
+
 <Note>
 Make sure you pass in the absolute path to your server.
 </Note>