接单平台分类管理完善：抢单大厅分类筛选与分类 CRUD

- 抢单大厅新增分类 Tab 筛选（仅显示启用分类，支持按分类查询工单）
- 管理端分类面板支持编辑、启用/停用切换、删除（被工单/规则引用时禁止删除）
- 后端工单列表支持 categoryId 筛选，大厅接口返回分类列表

apps/backend/src/services/worker-platform/worker-platform-service.ts

@@ -9,12 +9,15 @@ import {
   addWorkerWalletCredit,
   countWorkerAcceptedOrders,
   countWorkerActiveOrders,
+  countWorkCategoryUsages,
   createWorkOrder,
   createWorkOrderEvent,
   createWorkerFinanceRequest,
   createWorkerUser,
+  deleteWorkCategory,
   getWorkerFinanceRequestById,
   getWorkerFinanceRequestSummary,
+  getWorkCategoryById,
   getWorkerLevelById,
   getWorkerLevelByKey,
   getWorkerUserByInviteCode,
@@ -28,6 +31,7 @@ import {
   listPendingMaterialWorkOrdersByPlatformOrderId,
   listWorkerWalletLedgers,
   grabWorkOrder,
+  listWorkCategories,
   listWorkOrders,
   listWorkProductRules,
   listWorkerLevels,
@@ -627,17 +631,21 @@ export async function listWorkerHallOrders(query: JsonObject = {}, session: Work
   requireActiveWorkerSession(session)
   const page = normalizePage(query.page)
   const pageSize = normalizePageSize(query.pageSize)
+  const categoryId = normalizeOptionalId(query.categoryId)
   const { items, total } = await listWorkOrders({
     page,
     pageSize,
     status: WORK_ORDER_STATUS.OPEN,
     keyword: String(query.keyword || '').trim(),
+    categoryId: categoryId || 0,
   })
   const worker = await getRequiredWorker(session.workerId)
   const permissions = resolveWorkerPermissions(worker)
+  const categories = (await listWorkCategories()).map(mapWorkCategory)
   return {
     items: items.map((item) => mapWorkOrderForWorker(item, permissions)),
     pagination: { page, pageSize, total },
+    categories,
   }
 }
 
@@ -880,6 +888,28 @@ export async function saveAdminWorkCategory(payload: JsonObject = {}) {
   return { category: mapWorkCategory(category) }
 }
 
+export async function deleteAdminWorkCategory(categoryId: number | string) {
+  const category = await getWorkCategoryById(Number(categoryId))
+  if (!category) {
+    throw createHttpError('分类不存在', {
+      statusCode: 404,
+      errorCode: 'work_category_not_found',
+    })
+  }
+  const usages = await countWorkCategoryUsages(Number(categoryId))
+  if (usages.workOrderCount > 0 || usages.productRuleCount > 0) {
+    throw createHttpError(
+      `该分类已被 ${usages.workOrderCount} 个工单和 ${usages.productRuleCount} 条物品规则使用，无法删除，请先停用`,
+      {
+        statusCode: 409,
+        errorCode: 'work_category_in_use',
+      },
+    )
+  }
+  const { deleted } = await deleteWorkCategory(Number(categoryId))
+  return { deleted }
+}
+
 export async function saveAdminWorkerLevel(payload: JsonObject = {}) {
   const now = nowIso()
   const levelKey = String(payload.levelKey || payload.level_key || '').trim() || DEFAULT_LEVEL_KEY