feat: share popups draw repos and files like everywhere else

repoLabel draws a repo, or a file in it, with pathLabel: the repo icon
and colour. The share popups use it for what's shared, where it's
from and where it's saved, and are titled for what's shared
("Share .env", "Share 2 env files"), the key picker too.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

internal/ui/app/jump.go

@@ -138,6 +138,12 @@ func (m Model) pathLabel(kind provider.Kind, path []string, account string) stri
 	return label
 }
 
+// repoLabel draws a repo, or a file in it, as everywhere else: the repo
+// icon and colour, "app / apps/api/.env".
+func (m Model) repoLabel(repo string, file ...string) string {
+	return m.pathLabel(provider.KindRepo, append([]string{repo}, file...), "")
+}
+
 // sourceMatches reports whether src is the subscription or workspace r
 // links to.
 func sourceMatches(r ref.Ref, src provider.Source) bool {