refactor(frontend): create unified button and replace tooltip button

[hieptl]

• This change is worth documenting at https://docs.all-hands.dev/
• 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.

• TooltipButton 
• IconButton
• ActionButton 
• EditorActionButton 
• ModalButton
• SubmitButton 
• ChatSendButton 
• ChatStopButton 
• ChatPlayButton 
• ChatAddFileButton 
• BrandButton

Requirement:

Our codebase currently contains multiple button implementations. To improve consistency and maintainability, we need to introduce a unified button component that can support multiple use cases. In this ticket, we will focus on creating the unified button and replacing the existing tooltip button. Replacement of other button types will be handled in subsequent tasks once the unified component is validated.

Acceptance Criteria:

• A unified button component is implemented.
• The existing tooltip button is replaced with the unified button.

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

The PR updates the code to meet the A/C above.

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Link of any specific issues this addresses:

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To run this PR locally, use the following command:

GUI with Docker:

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:1347af3-nikolaik   --name openhands-app-1347af3   docker.all-hands.dev/all-hands-ai/openhands:1347af3

CLI with uvx:

uvx --python 3.12 --from git+https://github.com/All-Hands-AI/OpenHands@hieptl/all-3392-1 openhands