Suppress the webview's default right-click menu

Reload/Inspect Element no longer appear on uncontrolled right-clicks
in any window; text fields keep the system text menu.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ui/src/app/platform.ts

@@ -23,3 +23,14 @@ export const APP_MODE: 'main' | 'editor' | 'manager' =
 
 export const EDITOR_CONTEXT =
   typeof window !== 'undefined' ? (window.__APP_CTX as EditorOpenContext | undefined) : undefined;
+
+/**
+ * Kill the webview's default right-click menu (Reload, Inspect Element…)
+ * everywhere the app doesn't show its own native menu. Text fields keep the
+ * system text menu (cut/copy/paste, spelling).
+ */
+export function blockNativeContextMenu(event: Event): void {
+  const target = event.target as HTMLElement | null;
+  if (target?.closest('input, textarea, [contenteditable="true"]')) return;
+  event.preventDefault();
+}