Diagrams: hide answer-giving counts in quizzes (HideCounts); bar/pie slices take the colour named by their label

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/screens/QuizScreen.tsx

@@ -346,7 +346,7 @@ export function QuizScreen({ lessonId, nodeId }: { lessonId?: number; nodeId?: s
             <span className="text-xs font-medium text-muted">سوال {toFa(index + 1)}</span>
           </div>
           <h2 className="whitespace-pre-line text-base font-bold leading-8 text-ink"><MathText text={question.prompt} display /></h2>
-          {question.figure ? <div className="mt-3"><Diagram spec={question.figure} /></div> : null}
+          {question.figure ? <div className="mt-3"><Diagram spec={question.figure} hideCounts /></div> : null}
         </div>
 
         <div className={shortOptions ? 'grid grid-cols-2 gap-2.5' : 'flex flex-col gap-2.5'}>