feat(board): default pagination with optional infinite scroll and URL-based page routing

src/hooks/use-board-feed-page-size.ts

@@ -0,0 +1,20 @@
+import { useMemo } from 'react';
+import type { DirectoryCommunity } from './use-directories';
+import { computeGuiPostsPerPage, getBoardFeedPageSizeConstants, type CommunityWithPostsPerPage } from '../lib/utils/board-feed-pagination';
+
+export type BoardFeedPageSize = ReturnType<typeof getBoardFeedPageSizeConstants>;
+
+/**
+ * Compute board feed page-size values from directory community.
+ *
+ * - Single directory board: uses community.features.postsPerPage when valid numeric > 0
+ * - Missing metadata, non-directory board, /all, /subs, /mod: fallback 15
+ *
+ * Returns: guiPostsPerPage, maxGuiPages (10), paginationFeedPostsPerPage, infiniteFeedPostsPerPage
+ */
+export const useBoardFeedPageSize = (community?: DirectoryCommunity | null): BoardFeedPageSize => {
+  return useMemo(() => {
+    const guiPostsPerPage = computeGuiPostsPerPage(community as CommunityWithPostsPerPage | null | undefined);
+    return getBoardFeedPageSizeConstants(guiPostsPerPage);
+  }, [community]);
+};