fix(frontend): migrate type changes

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

frontend/src/components/render-page/hooks/sync-scroll/use-document-sync-scrolling.ts

@@ -26,10 +26,10 @@ export const useDocumentSyncScrolling = (
   outerContainerRef: React.RefObject<HTMLElement>,
   rendererRef: React.RefObject<HTMLElement>,
   numberOfLines: number,
-  scrollState?: ScrollState,
-  onScroll?: (scrollState: ScrollState) => void
+  scrollState: ScrollState | null,
+  onScroll: null | ((scrollState: ScrollState) => void)
 ): [(lineMarkers: LineMarkerPosition[]) => void, React.UIEventHandler<HTMLElement>] => {
-  const [lineMarks, setLineMarks] = useState<LineMarkerPosition[]>()
+  const [lineMarks, setLineMarks] = useState<LineMarkerPosition[]>([])
 
   const recalculateLineMarkerPositions = useCallback(
     (linkMarkerPositions: LineMarkerPosition[]) => {

frontend/src/components/render-page/hooks/sync-scroll/use-on-user-scroll.ts

@@ -19,7 +19,7 @@ import { useCallback } from 'react'
 export const useOnUserScroll = (
   lineMarks: LineMarkerPosition[] | undefined,
   scrollContainer: React.RefObject<HTMLElement>,
-  onScroll: ((newScrollState: ScrollState) => void) | undefined
+  onScroll: ((newScrollState: ScrollState) => void) | null
 ): React.UIEventHandler<HTMLElement> => {
   return useCallback(() => {
     if (!scrollContainer.current || !lineMarks || lineMarks.length === 0 || !onScroll) {

frontend/src/components/render-page/hooks/sync-scroll/use-scroll-to-line-mark.ts

@@ -18,8 +18,8 @@ import { useCallback, useEffect, useRef } from 'react'
  * @param scrollContainer The container to scroll in
  */
 export const useScrollToLineMark = (
-  scrollState: ScrollState | undefined,
-  lineMarks: LineMarkerPosition[] | undefined,
+  scrollState: ScrollState | null,
+  lineMarks: LineMarkerPosition[],
   contentLineCount: number,
   scrollContainer: RefObject<HTMLElement>
 ): void => {