Omit hidden worktrees when showing projects in collaboration UI

crates/collab/src/db.rs

@@ -1924,10 +1924,12 @@ impl Database {
                 };
 
                 if let Some(db_worktree) = db_worktree {
+                    if db_worktree.visible {
                         project.worktree_root_names.push(db_worktree.root_name);
                     }
                 }
             }
+        }
 
         Ok(proto::Room {
             id: db_room.id.to_proto(),