[front] Implement screenshot downloader for recharts-based graphs

[alexeyeryshev]

Description

This PR adds a button to the vizualization-powered graph generated with recharts if they can be exported as an SVG.
It works by adding a button to viz wrapper and using event source API to pass the Blob to the main dust frontend app.

The download button needs some love to style.

Screen.Recording.2024-08-21.at.17.31.40.mov

Risk

Safe to rollback.

Deploy Plan

1. Deploy frotnend
2. Use an assistant with viz enabled to verify the functionality
3. Ask it to generate a simple graph with recharts, check for the download button and that it does what you expect it to.
4. Ask it to generete a todo app - the download button shouldn't be shown.