river/tags: fix memory leak of output_status_/seat_status_

The constructor created output_status_ and seat_status_ without adding any
listener, then handle_show() recreated both (leaking the constructor-created
objects) before destroying status_manager_. Additionally seat_status_ was
never destroyed in ~Tags().

Create these objects lazily (with listeners) only in handle_show(), and
destroy seat_status_ in the destructor.

src/modules/river/tags.cpp

@@ -138,9 +138,10 @@ Tags::Tags(const std::string& id, const waybar::Bar& bar, const Json::Value& con
     return;
   }
 
+  // Store the output this module belongs to; the river_output_status and
+  // river_seat_status objects (and their listeners) are created lazily in
+  // handle_show() to avoid leaking objects without listeners here.
   output_ = gdk_wayland_monitor_get_wl_output(bar_.output->monitor->gobj());
-  output_status_ = zriver_status_manager_v1_get_river_output_status(status_manager_, output_);
-  seat_status_ = zriver_status_manager_v1_get_river_seat_status(status_manager_, seat_);
 
   box_.set_name("tags");
   if (!id.empty()) {
@@ -193,6 +194,10 @@ Tags::~Tags() {
     zriver_output_status_v1_destroy(output_status_);
   }
 
+  if (seat_status_) {
+    zriver_seat_status_v1_destroy(seat_status_);
+  }
+
   if (control_) {
     zriver_control_v1_destroy(control_);
   }