Add dev mode for previewing components

[VictoriaBeilsten-Edmands]

No description provided.

[akademy]

This looks great, but wondering if we reference the package, rather than the individual components.

I add this to package.json

"@diamondlightsource/sci-react-ui": "file://../",

Then reference the components as usual.

import { Bar } from '@diamondlightsource/sci-react-ui';`

which seemed to work, but I'm getting odd typescript errors for the components.

[akademy]

Actually, it's not a big deal. Maybe we can look into it some other time.

I'll approve.

[akademy]

Looks good. A future update should include a kitchen sink...!