feat: disable browser spell check in report editor

- Add spellCheck={false} prop to PlateContent component in Editor.tsx
- Follows established pattern from CodeBlockNode.tsx
- Fixes BUS-1866: Removes red wavy underlines under misspelled words
- Applies globally to all report editor instances

Co-Authored-By: nate@buster.so <nate@buster.so>

apps/web/src/components/ui/report/Editor.tsx

@@ -43,6 +43,7 @@ export const Editor = React.forwardRef<HTMLDivElement, EditorProps>(
     return (
       <PlateContent
         ref={ref}
+        spellCheck={false}
         className={cn(
           editorVariants({
             readOnly,