Warn about Search index cap when user has requested more than a 1000 results #3839
Description
When using gh pr list --limit N --label foo, only 1000 results will get returned at maximum, even if the user requested N > 1000.
This is because we switch to the Search API for --label lookups #3295, and the Search API only ever returns a maximum of 1000 results, even with pagination.
We could try providing some warning on stderr when --limit was used with a value greater than 1,000 and when the resulting query will be backed by search.
Originally posted by @mislav in #3836 (comment)