feat: streaming bash command output

[ryanhoangt]

• [ ] This change is worth documenting at https://docs.all-hands.dev/
• [x] Include this change in the Release Notes. If checked, you must provide an end-user friendly description for your change below

End-user friendly description of the problem this fixes or functionality this introduces. Add support for streaming bash command outputs.

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Summarize what the PR does, explaining any non-trivial design decisions.

This PR adds support for streaming bash command output via a new SSE endpoint, which is consumed by the "Terminal" tab in the UI.

Demo:

https://github.com/user-attachments/assets/5f688983-cf23-40f0-a1a9-7fab9bb00f55

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Link of any specific issues this addresses: Close #5213

[github-actions[bot]]

This PR is stale because it has been open for 30 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[github-actions[bot]]

This PR is stale because it has been open for 30 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[xingyaoww]

@ryanhoangt can you fix the merge conflict and maybe we can get it merged?

[ryanhoangt]

@OpenHands /codereview

[openhands-ai[bot]]

I'm on it! ryanhoangt can track my progress at all-hands.dev

[github-actions[bot]]

This PR is stale because it has been open for 40 days with no activity. Remove the stale label or leave a comment, otherwise it will be closed in 10 days.

[github-actions[bot]]

This PR was closed because it had no activity for 50 days. If you feel this was closed in error, and you would like to continue the PR, please resubmit or let us know.