feat: wireplumber support

Adds basic support for showing volume via wireplumber. Allows specifying
the node-id or falling back to the default Audio/Sink node id if node-id
is not set. If tooltip on hover is enabled, will show `{node_name}` by
default otherwise `tooltip-format`.

Format replacements:

`{volume}` - Volume in percentage
`{node_name}` - The node's nickname (`node.nick` property)

include/modules/wireplumber.hpp

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <fmt/format.h>
+#include <wp/wp.h>
+
+#include <algorithm>
+#include <array>
+
+#include "AButton.hpp"
+
+namespace waybar::modules {
+
+class Wireplumber : public AButton {
+  public:
+   Wireplumber(const std::string&, const Json::Value&);
+   ~Wireplumber();
+   auto update() -> void;
+
+  private:
+   void loadRequiredApiModules();
+   void prepare();
+   void activatePlugins();
+   static void updateVolume(waybar::modules::Wireplumber* self);
+   static void updateNodeName(waybar::modules::Wireplumber* self);
+   static uint32_t getDefaultNodeId(waybar::modules::Wireplumber* self);
+   static void onPluginActivated(WpObject* p, GAsyncResult* res, waybar::modules::Wireplumber* self);
+   static void onObjectManagerInstalled(waybar::modules::Wireplumber* self);
+   
+   WpCore* wp_core_;
+   GPtrArray* apis_;
+   WpObjectManager* om_;
+   uint32_t pending_plugins_;
+   bool muted_;
+   double volume_;
+   uint32_t node_id_{0};
+   std::string node_name_;
+
+};
+
+} // namespace waybar::modules