feat: add VSCode to OpenHands runtime and UI

[xingyaoww]

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

• 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

Add VSCode based on https://github.com/gitpod-io/openvscode-server, so we can quickly pop up an editor on UI to play around with files and download them properly (the current download zip in UI doesn't work too well)

openhands-vscode.mp4

TODO:

• We need to pop up a warning when people try to click VSCode in FE when the runtime is not initialize yet
• We need to show the info to the user: "The agent currently is unaware of changes you've made in VSCode. Please let the agent know the changes you've made. Please try not to work at the same time as the agent."

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Link of any specific issues this addresses

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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:718693d-nikolaik   --name openhands-app-718693d   docker.all-hands.dev/all-hands-ai/openhands:718693d