Refresh search results after switching mine

If you return to the search page after running a keyword search on a different mine, it will still show the old results with broken links.

*Medium priority as you can only enter the search page without starting a new search, by using the Search navbar button only shown on narrow screens.*

Reproduce the flow by searching on one mine, switching to another, and returning through the Search navbar button on a narrow screen. Trace the search-page entry point and its result-loading behavior; done means the page no longer shows stale results or broken links after switching mines.

Written by the indexing model from the issue text.