docs: broken jsonpath in quick-start.md "Verify Kmesh Service Logs" command

Problem:
In the Quick Start guide (docs/setup/quick-start.md), under "4. Verify Kmesh Service Logs", the command is:

kubectl logs -n kmesh-system $(kubectl get pods -n kmesh-system -o jsonpath='{.items.metadata.name}')

`.items` is a JSON array (kubectl get pods returns multiple pods), so `.items.metadata.name` is invalid jsonpath syntax without an index or wildcard. Running this command as written returns empty output or an error, so this step fails for anyone following the quick-start guide verbatim.

Expected fix:
Should be either:

kubectl logs -n kmesh-system $(kubectl get pods -n kmesh-system -o jsonpath='{.items[0].metadata.name}')

(for the first pod) or use a label selector to target the Kmesh pod specifically.

Additional context:
I'd like to work on this - happy to submit a PR with the fix.