fix(frontend): Prevent VSCode from opening when remounting

[amanape]

End-user friendly description of the problem this fixes or functionality that this introduces

• VSCode URL would forcefully open in certain cases such as when the query handler is remounted (due to the use effect logic)

• Include this change in the Release Notes. If checked, you must provide an end-user friendly description for your change below

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Give a summary of what the PR does, explaining any non-trivial design decisions

• Fetches the URL when necessary, but only open the URL when the user explicitly clicks the handler

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Link of any specific issues this addresses
Resolves #5519

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To run this PR locally, use the following command:

docker run -it --rm   -p 3000:3000   -v /var/run/docker.sock:/var/run/docker.sock   --add-host host.docker.internal:host-gateway   -e SANDBOX_RUNTIME_CONTAINER_IMAGE=docker.all-hands.dev/all-hands-ai/runtime:d848ea0-nikolaik   --name openhands-app-d848ea0   docker.all-hands.dev/all-hands-ai/openhands:d848ea0

[xingyaoww]

Thanks a lot for the fix!

[diwu-sf]

Thanks!!!