Insight: Add visualisation tab to the search result page side panel

Created by: vovakulikov

Part of https://github.com/sourcegraph/sourcegraph/issues/38430

We should add visualisation tab (related Figma desings) to the result search page sidebar with historical trend chart. This chart and visualization tab is a part of "simple UI" mode so it should appear only when the experimental flag is on and when simple UI is on as well.