fix(api): hide limited users from restricted viewers (#39004) (#39039)

Backport #39004 by @bircni

Use the canonical profile-visibility check for user API content and
prevent restricted users from enumerating public repositories owned by
limited users.

This keeps feeds, heatmaps, keys, and issue search consistent with
profile visibility.

Co-authored-by: bircni <bircni@icloud.com>
Co-authored-by: silverwind <me@silverwind.io>

models/issues/issue_search.go

@@ -220,7 +220,7 @@ func applyRepoConditions(sess db.Session, opts *IssuesOptions) {
 		if opts.RepoCond == nil {
 			opts.RepoCond = builder.NewCond()
 		}
-		opts.RepoCond = opts.RepoCond.Or(builder.In("issue.repo_id", builder.Select("id").From("repository").Where(builder.Eq{"is_private": false})))
+		opts.RepoCond = opts.RepoCond.Or(builder.In("issue.repo_id", builder.Select("id").From("repository").Where(repo_model.PublicRepoUnderPublicOwnerCond())))
 	}
 	if opts.RepoCond != nil {
 		sess.And(opts.RepoCond)