feat: 增加友链申请、独立页面、投票/悬赏/抽奖帖与侧栏签到，并统一开发数据目录

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/utils/sortOrder.ts

@@ -0,0 +1,69 @@
+import { arrayMove } from '@dnd-kit/sortable';
+
+export const ADMIN_SORTABLE_MOVE_BUTTONS_THRESHOLD = 8;
+
+export function reorderItems<T>(items: T[], from: number, to: number): T[] {
+  if (from < 0 || to < 0 || from >= items.length || to >= items.length || from === to) {
+    return items;
+  }
+  return arrayMove(items, from, to);
+}
+
+export function assignSortOrders<T extends { sort_order?: number }>(items: T[]): T[] {
+  return items.map((item, index) => ({ ...item, sort_order: index + 1 }));
+}
+
+export function diffSortOrderChanges<T extends { id: number; sort_order?: number }>(
+  before: T[],
+  after: T[],
+): Array<{ id: number; sort_order: number }> {
+  const beforeMap = new Map(before.map(item => [item.id, item.sort_order ?? 0]));
+  return after
+    .filter(item => beforeMap.get(item.id) !== item.sort_order)
+    .map(item => ({ id: item.id, sort_order: item.sort_order ?? 0 }));
+}
+
+/** 将子集重排结果合并回完整列表，并重算 sort_order */
+export function mergeReorderedSubset<T extends { id: number; sort_order?: number }>(
+  all: T[],
+  subsetBefore: T[],
+  subsetAfter: T[],
+): T[] {
+  const sorted = [...all].sort((a, b) => (a.sort_order ?? 0) - (b.sort_order ?? 0) || a.id - b.id);
+  const subsetIds = new Set(subsetBefore.map(item => item.id));
+  const result: T[] = [];
+  let subsetIdx = 0;
+  for (const item of sorted) {
+    if (subsetIds.has(item.id)) {
+      if (subsetIdx < subsetAfter.length) {
+        result.push(subsetAfter[subsetIdx++]);
+      }
+    } else {
+      result.push(item);
+    }
+  }
+  return assignSortOrders(result);
+}
+
+export async function persistSortOrderChanges<T extends { id: number; sort_order?: number }>(
+  before: T[],
+  reordered: T[],
+  updateItem: (item: T) => Promise<void>,
+): Promise<T[]> {
+  const after = assignSortOrders(reordered);
+  const changes = diffSortOrderChanges(before, after);
+  for (const change of changes) {
+    const item = after.find(row => row.id === change.id);
+    if (item) await updateItem(item);
+  }
+  return after;
+}
+
+export function shouldShowSortableMoveButtons(
+  count: number,
+  mode: boolean | 'auto' = 'auto',
+): boolean {
+  if (mode === true) return true;
+  if (mode === false) return false;
+  return count > ADMIN_SORTABLE_MOVE_BUTTONS_THRESHOLD;
+}