plugin: anchor cxx-qt plugin init symbol so the linker keeps QQmlEngineExtensionPlugin

plugin/src/lib.rs

@@ -2,9 +2,19 @@ pub mod cpu_service;
 pub mod stats;
 pub mod system_stats;
 
-// Fires when the .so is dlopen'd. Tells us the plugin file actually loaded,
-// independent of whether qml_register_types runs.
+// cxx-qt-build emits a QQmlEngineExtensionPlugin C++ class with Q_PLUGIN_METADATA
+// alongside an `init_cxx_qt_qml_module_<name>_plugin()` symbol whose only purpose is
+// to anchor that translation unit. Without referencing it from Rust, the linker
+// drops the .o containing the plugin class - Qt then dlopens the .so, finds no
+// plugin metadata, and never calls qml_register_types_NovaStats.
+unsafe extern "C" {
+    fn init_cxx_qt_qml_module_NovaStats_plugin() -> bool;
+}
+
 #[ctor::ctor(unsafe)]
 fn on_dylib_load() {
     eprintln!("[nova-plugin] dylib loaded (libNovaStats.so)");
+    unsafe {
+        init_cxx_qt_qml_module_NovaStats_plugin();
+    }
 }