Fix undefined variable 'opts' in getSidebarCategoriesT function (#31815)

The function was trying to use 'opts.TeamID' but 'opts' was not defined in the function scope. Changed it to use the 'teamId' parameter which is properly defined in the function signature.

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Co-authored-by: Claude <noreply@anthropic.com>

server/channels/store/sqlstore/channel_store_categories.go

@@ -568,7 +568,7 @@ func (s SqlChannelStore) getSidebarCategoriesT(db sqlxExecutor, userId, teamId s
 		}
 	}
 
-	if _, err := s.completePopulatingCategoriesT(db, userId, opts.TeamID, oc.Categories); err != nil {
+	if _, err := s.completePopulatingCategoriesT(db, userId, teamId, oc.Categories); err != nil {
 		return nil, err
 	}