feat(experiments): add delta chart

[jurajmajerik]

Feature flag: experiments-multiple-metrics

Changes

The first iteration of the delta chart. I initially tried building it with Chart.js but after some frustration, switched to good old plain SVG.

Also added a logic loader to fetch all metrics, called behind the same feature flag. I’ll add the ability to add/edit multiple primary metrics in a follow up.

How did you test this code?

👀

[github-actions[bot]]

Size Change: +60 B (+0.01%)

Total Size: 1.16 MB

ℹ️ View Unchanged

| Filename | Size | Change | | :--- | :---: | :---: | | `frontend/dist/toolbar.js` | 1.16 MB | +60 B (+0.01%) |

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