fix remaining build errors

src/components/player/PlayerBottomBar.tsx

@@ -34,7 +34,7 @@ interface Props {
   volume: number
   loopA: number | null
   loopB: number | null
-  chapters: { StartPositionTicks: number; Name?: string | null; ImageTag?: string | null }[]
+  chapters: { StartPositionTicks?: number | null; Name?: string | null; ImageTag?: string | null }[]
   bookmarksRefreshKey: number
   previousItem: BaseItemDto | null | undefined
   nextItem: BaseItemDto | null | undefined

src/components/player/PlayerOverlays.tsx

@@ -11,7 +11,7 @@ import SyncPlayPanel from './SyncPlayPanel'
 import type { BaseItemDto } from '../../api/types'
 
 export interface ChapterMarker {
-  StartPositionTicks: number
+  StartPositionTicks?: number | null
   Name?: string | null
   ImageTag?: string | null
 }