Pass plugin path around instead of redetecting

This is now set only once at the top level. This is needed for the
chainloading to work because we'll need to set the path when we create
the bridge.

src/plugin/utils.h

@@ -58,6 +58,9 @@ struct PluginInfo {
      *
      * @param plugin_type The type of the plugin we're going to load. The
      *   detection works slightly differently depending on the plugin type.
+     * @param plugin_path The path to the **native** plugin library `.so` file.
+     *   This is used to determine the path to the Windows plugin library we
+     *   should load.
      * @param prefer_32bit_vst3 If there's both a 64-bit and a 32-bit Windows
      *   VST3 module in the same bundle, then setting this to true will cause
      *   the 32-bit version to be used instead of the 64-bit version.
@@ -66,7 +69,9 @@ struct PluginInfo {
      *   plugin. The error message contains a human readable description of what
      *   went wrong.
      */
-    PluginInfo(PluginType plugin_type, bool prefer_32bit_vst3 = false);
+    PluginInfo(PluginType plugin_type,
+               const ghc::filesystem::path& plugin_path,
+               bool prefer_32bit_vst3 = false);
 
     /**
      * Create the environment for the plugin host based on `wine_prefix_`. If
@@ -267,15 +272,16 @@ Configuration load_config_for(const ghc::filesystem::path& yabridge_path);
  * @param body The message to display. This can contain line feeds, and it any
  *   HTML tags and XML escape sequences will be automatically escaped. The
  *   message can also be empty.
- * @param Whether to append 'Source: <XXX.so>' to the body, where `<XXX.so>` is
- *   a hyperlink to the directory this library is placed in.
+ * @param origin If this is set to the current plugin's path, then the
+ *   notification will append a 'Source: <XXX.so>' hyperlink to the body so the
+ *   user can more easily navigate to the plugin's path.
  *
  * @return Whether the notification was sent. This will be false if
  *   `notify-send` is not available.
  */
 bool send_notification(const std::string& title,
                        const std::string body,
-                       bool append_origin);
+                       std::optional<ghc::filesystem::path> origin);
 
 /**
  * Starting from the starting file or directory, go up in the directory