fix(web): hide unsupported plugin manager

Fixes #567

src/app/commands/view.rs

@@ -212,10 +212,17 @@ impl OpenCADStudio {
                 return Some(Task::done(Message::AboutOpen));
             }
 
+            #[cfg(not(target_arch = "wasm32"))]
             "PLUGINS" | "PLUGINMANAGER" => {
                 return Some(Task::done(Message::PluginManagerOpen));
             }
 
+            #[cfg(target_arch = "wasm32")]
+            "PLUGINS" | "PLUGINMANAGER" => {
+                self.command_line
+                    .push_info("External plugins are available in the desktop app.");
+            }
+
             "CHANGELOG" => {
                 crate::sys::open_url("https://github.com/HakanSeven12/OpenCADStudio/releases");
                 self.command_line.push_info("Opening release notes...");