fixes TAN-1065. a ticket with a target branch is a pull request, and opening it under /issues/<rkey> showed "Issue not found". it now redirects to /pulls/<rkey>.
- server: the issue page returns
kind: "pull"for a ticket with a target branch and redirects with a 307 - client navigation: the page calls
gototo the pull url withreplaceState, so back does not return to the dead url pulls/[rkey]layout redirects the other way when the ticket has no target branch
/tangled.org/core/issues/4644 is pull request 4644. before, it is a not found page. after, it lands on the pull request: