fix(mobile): apply useModalStyle to 7 more modal dialogs

ScheduleMessageModal, PollCreator, JoinAddressPrompt, JumpToTime,
EditHistoryModal, ForwardMessageDialog, RemindMeDialog — all now
render fullscreen on mobile (≤750px) and as a capped-width box on
desktop, consistent with the existing useModalStyle pattern.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/features/room/ScheduleMessageModal.tsx

@@ -19,6 +19,7 @@ import { IContent } from 'matrix-js-sdk';
 import { useMatrixClient } from '../../hooks/useMatrixClient';
 import { stopPropagation } from '../../utils/keyboard';
 import { scheduleMessage } from '../../utils/scheduledMessages';
+import { useModalStyle } from '../../hooks/useModalStyle';
 
 interface ScheduleMessageModalProps {
   roomId: string;
@@ -89,6 +90,7 @@ export function ScheduleMessageModal({
   onScheduled,
   onClose,
 }: ScheduleMessageModalProps) {
+  const modalStyle = useModalStyle(400);
   const mx = useMatrixClient();
   const [messageText, setMessageText] = useState(initialBody ?? '');
   const [submitting, setSubmitting] = useState(false);
@@ -186,9 +188,7 @@ export function ScheduleMessageModal({
               background: color.Surface.Container,
               borderRadius: config.radii.R400,
               boxShadow: color.Other.Shadow,
-              width: '100vw',
-              maxWidth: 400,
-              overflow: 'hidden',
+              ...modalStyle,
             }}
           >
             {/* Header */}