Disentangle search tour code from MonacoQueryInput

Created by: lguychard

There is currently a lot of code that is search tour specific in our MonacoQueryInput component: https://sourcegraph.com/github.com/sourcegraph/sourcegraph@5422317dc386f2ee89becd622e0b06a4c9bad2ff/-/blob/client/web/src/search/input/MonacoQueryInput.tsx?subtree=true#L352-425

Ideally this should be extracted out of the component, as we may want to reuse the MonacoQueryInput elsewhere in the application, and not just as our global search input (eg. #17320 (closed)). Maybe extract into something like a <SearchTour/> HOC?