Sweep targeted typecheck errors: 11 fixes across 9 files

- ProductImageUtility: 'CatalogPageMessageProductData.I' was clearly a
  placeholder/typo in the WALL branch — getProductCategory's first
  param is FurnitureType, so use the enclosing productType.
- YouTubePlayerView: IRoomUserData has webID, not userId. Two
  spectator/watcher-list sites used the wrong field.
- AvatarInfoWidgetView REQUEST_MANIPULATION handler: avatarInfo is
  IAvatarInfo (union); .category / .id only exist on AvatarInfoFurni.
  Type-guard before reading.
- InfoStandWidgetPetView: deleted the duplicate local 'interface
  AvatarInfoPet' — was shadowing the imported one. Drop AvatarInfoPet
  from the import (local interface stands alone).
- FurnitureExternalImageView: missing GetSessionDataManager import (the
  reportedUserId field reads it inline). Added.
- GroupCreatorView setGroupData call: null values for groupName /
  groupDescription / groupColors / groupBadgeParts where IGroupData
  expects string / number[] / GroupBadgePart[]. Empty defaults. Also
  added the previously-omitted groupHasForum field.
- ContextMenuView + WiredCreatorToolsView: 'return () =>
  ticker.remove(updateOverlays)' — Pixi Ticker.remove() returns the
  ticker, leaking the value to React's EffectCallback cleanup which
  expects 'void | (() => void)'. Wrap in block body.
- Deleted src/components/room/widgets/chat/ChatWidgetWindowView_old.tsx
  — dead code (zero references in the codebase), tripping the
  NitroCardHeaderView onCloseClick prop change.

Net tsgo error count: -11.

src/components/groups/views/GroupCreatorView.tsx

@@ -108,13 +108,14 @@ export const GroupCreatorView: FC<GroupCreatorViewProps> = props =>
 
         setGroupData({
             groupId: -1,
-            groupName: null,
-            groupDescription: null,
+            groupName: '',
+            groupDescription: '',
             groupHomeroomId: -1,
             groupState: 1,
             groupCanMembersDecorate: true,
-            groupColors: null,
-            groupBadgeParts: null
+            groupHasForum: false,
+            groupColors: [],
+            groupBadgeParts: []
         });
 
         SendMessageComposer(new GroupBuyDataComposer());