Track which results are clicked in Global Search

What does this MR do and why?

This Mr changes legacy tracking of the search page results to the new internal event tracking so we can better organise and chart resulting data.

This is just one event click_search_result it will have label, value, property attribute set.

label: search result scope
value: result position
property: search term

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Visit search page: http://gdk.test:3000/search
2. Search anything e.g. *
3. check all types of results are reporting

Related to #407593