fix: stabilize renderer state and lifecycle updates

Prevent stale history, account, diagnostics, and language updates from repainting newer state. Keep queue virtualization, panel sizing, telemetry, cancellation, and runtime timing consistent across rapid UI changes. Strengthen painted-frame and lifecycle regression coverage, and brand packaged Windows metadata with the product publisher.

lib/startup-renderer.js

@@ -4,6 +4,10 @@ function configureStartupRenderer(app, env = process.env, platform = process.pla
   return app;
 }
 
+function resolveStartupLanguage(config) {
+  return config && config.globalSettings && config.globalSettings.language === 'de' ? 'de' : 'en';
+}
+
 function createStartupWindow(BrowserWindow, options) {
   const window = new BrowserWindow({ ...options, show: false });
   window.once('ready-to-show', () => {
@@ -12,10 +16,10 @@ function createStartupWindow(BrowserWindow, options) {
 
   return {
     window,
-    load(target, onLoadError) {
-      return window.loadFile(target).catch(onLoadError);
+    load(target, onLoadError, options) {
+      return window.loadFile(target, options).catch(onLoadError);
     }
   };
 }
 
-module.exports = { configureStartupRenderer, createStartupWindow };
+module.exports = { configureStartupRenderer, createStartupWindow, resolveStartupLanguage };