docs: clarify queryClient refetch behavior for stale queries

[imadselka]

This pull request updates the documentation for the useRefreshOnFocus custom hook in the React Native guide to clarify its behavior and improve its implementation. The hook now refetches all active stale queries on screen focus, rather than requiring a specific refetch function to be passed in.

Documentation and code improvements:

• Updated the description and implementation of useRefreshOnFocus to indicate that it refetches all active stale queries when the screen is focused, using queryClient.refetchQueries instead of a provided refetch function. [1] [2]
• Clarified the explanation about skipping the first focus to reflect the new implementation and behavior.

[TkDodo]

i was more thinking to have this directly in the react native example instead of calling refetch() like we recommend now?

[imadselka]

yes you are right , i changed it .
but another thing do you think we should add it in the main refetchQueries docs like this

// refetch all stale queries: 
await queryClient.refetchQueries({ stale: true })

// refetch only stale queries that are currently active (recommended for RN screen-focus)
await queryClient.refetchQueries({ stale: true, type: 'active' })

[heisenbugged]

my recommendation here is to still pass in a query key so it's refresh on focus tied to a specific query rather than a blanket refresh everything