spike: Web Charts: Expose chart UI building blocks together with built-in high level charts

Created by: vovakulikov

Preparation for https://github.com/sourcegraph/sourcegraph/issues/36094

Background

Currently, we expose only high-level chart components from the chart package. This brings a significant benefit in that consumers don't need to think about how to implement all chart UI parts themselves. But at the same time, this approach blocks us from high-level customisations in charts. Like adding additional data with particular styles, with unique hover and tooltip content. More on this in this comment https://github.com/sourcegraph/sourcegraph/issues/36094#issuecomment-1192357209

In this issue, we should develop building blocks API and expose it together with high-level charts from the chart package. This will allow them to build their charts by re-using complicated chart parts but bringing their custom content.

We don't need to refactor the whole chart codebase for it. Some part of this has been done in this PR about axis components https://github.com/sourcegraph/sourcegraph/pull/39805.

/cc @joelkw @felixfbecker @vovakulikov @unclejustin