Add a general entry point to HostBridge

Since for all plugin types we would need to start listening for incoming
events this way.

src/wine-host/bridges/common.h

@@ -25,6 +25,21 @@
  */
 class HostBridge {
    public:
+    virtual ~HostBridge(){};
+
+    /**
+     * Handle events until the plugin exits. The actual events are posted to
+     * `main_context` to ensure that all operations to could potentially
+     * interact with Win32 code are run from a single thread, even when hosting
+     * multiple plugins. The message loop should be run on a timer within the
+     * same IO context.
+     *
+     * @note Because of the reasons mentioned above, for this to work the plugin
+     *   should be initialized within the same thread that calls
+     *   `main_context.run()`.
+     */
+    virtual void run() = 0;
+
     /**
      * Handle X11 events for the editor window if it is open. This can safely be
      * run from any thread.

src/wine-host/bridges/group.cpp

@@ -116,7 +116,7 @@ void GroupBridge::handle_plugin_dispatch(size_t plugin_id) {
 
     // Blocks this thread until the plugin shuts down, handling all events on
     // the main IO context
-    bridge->handle_dispatch();
+    bridge->run();
     logger.log("'" + bridge->vst_plugin_path.string() + "' has exited");
 
     // After the plugin has exited we'll remove this thread's plugin from the

src/wine-host/bridges/vst2.cpp

@@ -271,7 +271,7 @@ Vst2Bridge::Vst2Bridge(MainContext& main_context,
     });
 }
 
-void Vst2Bridge::handle_dispatch() {
+void Vst2Bridge::run() {
     sockets.host_vst_dispatch.receive_events(
         std::nullopt, [&](Event& event, bool /*on_main_thread*/) {
             if (event.opcode == effProcessEvents) {

src/wine-host/bridges/vst2.h

@@ -62,18 +62,7 @@ class Vst2Bridge : public HostBridge {
                std::string plugin_dll_path,
                std::string endpoint_base_dir);
 
-    /**
-     * Handle events until the plugin exits. The actual events are posted to
-     * `main_context` to ensure that all operations to could potentially
-     * interact with Win32 code are run from a single thread, even when hosting
-     * multiple plugins. The message loop should be run on a timer within the
-     * same IO context.
-     *
-     * @note Because of the reasons mentioned above, for this to work the plugin
-     *   should be initialized within the same thread that calls
-     *   `main_context.run()`.
-     */
-    void handle_dispatch();
+    void run() override;
 
     /**
      * Forward the host callback made by the plugin to the host and return the