[feat] negosium: 협상 리스트 마감기준 정렬 컨트롤

- SortControl(기본순/마감임박순/여유순) 추가, StatusTabs 우측에 배치
- store setDeadline 배선 — 선택값을 서버 정렬(deadlineToOrder)로 전달

frontend/src/features/list/components/SortControl.tsx

@@ -0,0 +1,37 @@
+import { cn } from '@/lib'
+
+// 마감 기준 정렬. value(null=기본 그룹정렬)는 store.selectedDeadline 로 그대로 전달되고,
+// adapter.deadlineToOrder 가 '남은 시간 적은 순'=asc(임박), 그 외=desc(여유) 로 매핑한다.
+const SORT_OPTIONS: { label: string; value: string | null }[] = [
+  { label: '기본순', value: null },
+  { label: '마감임박순', value: '남은 시간 적은 순' },
+  { label: '여유순', value: '남은 시간 긴 순' },
+]
+
+interface SortControlProps {
+  selected: string | null
+  onSelect: (value: string | null) => void
+}
+
+export function SortControl({ selected, onSelect }: SortControlProps) {
+  return (
+    <div className="flex items-center gap-0.5 rounded-xl border border-border bg-neutral-10 p-0.5">
+      {SORT_OPTIONS.map((o) => {
+        const active = selected === o.value
+        return (
+          <button
+            key={o.label}
+            type="button"
+            onClick={() => onSelect(o.value)}
+            className={cn(
+              'whitespace-nowrap rounded-[10px] px-2.5 py-[6px] text-xs font-bold transition-all active:scale-[0.98]',
+              active ? 'bg-white text-brand-700 shadow-sm' : 'text-neutral-60 hover:text-neutral-80',
+            )}
+          >
+            {o.label}
+          </button>
+        )
+      })}
+    </div>
+  )
+}

frontend/src/features/list/containers/ListWorkspace.tsx

@@ -15,6 +15,7 @@ import { useList } from '@/features/list/hooks/useList'
 import { useListStore } from '@/features/list/stores/useListStore'
 import { KpiCards } from '@/features/list/components/KpiCards'
 import { StatusTabs } from '@/features/list/components/StatusTabs'
+import { SortControl } from '@/features/list/components/SortControl'
 import { WorkspaceTable } from '@/features/list/components/WorkspaceTable'
 import { WorkspaceCards } from '@/features/list/components/WorkspaceCards'
 import { Pagination } from '@/features/list/components/Pagination'
@@ -35,19 +36,22 @@ const REJECT_BLOCKED: Record<string, string> = {
 export function ListWorkspace() {
   const navigate = useNavigate()
   const { data: user } = useMeQuery()
-  // 리스트는 서버 페이징. (검색은 백엔드 미지원 → 프론트 검색은 비워 둠)
+  // 리스트는 서버 페이징 + 서버 검색(keyword: 견적번호·상품명·상품코드 부분일치).
   const { items, isLoading, totalPages, currentPage, setCurrentPage } = useList()
   const participate = useParticipateMutation()
   const reject = useRejectMutation()
   const saveExtra = useSaveExtraInfoMutation()
   const requestRenego = useRequestRenegotiationMutation()
 
-  const { selectedStatus, selectedResult, setStatus, toggleResult, setKeyword } = useListStore(
+  const { selectedStatus, selectedResult, selectedDeadline, setStatus, toggleResult, setDeadline, setKeyword } =
+    useListStore(
       useShallow((s) => ({
         selectedStatus: s.selectedStatus,
         selectedResult: s.selectedResult,
+        selectedDeadline: s.selectedDeadline,
         setStatus: s.setStatus,
         toggleResult: s.toggleResult,
+        setDeadline: s.setDeadline,
         setKeyword: s.setKeyword,
       })),
     )
@@ -153,6 +157,7 @@ export function ListWorkspace() {
         <div className="flex flex-col gap-3 border-b border-border p-4 lg:flex-row lg:items-center lg:justify-between">
           <StatusTabs selected={selectedStatus} onSelect={setStatus} />
           <div className="flex w-full items-center gap-2 lg:w-auto">
+            <SortControl selected={selectedDeadline} onSelect={setDeadline} />
             <div className="relative flex-1 lg:flex-none">
               <Search className="pointer-events-none absolute left-2.5 top-1/2 size-3.5 -translate-y-1/2 text-neutral-50" />
               <input

frontend/src/features/list/stores/useListStore.ts

@@ -13,6 +13,7 @@ interface ListState {
   toggleStatus: (item: string) => void
   setStatus: (item: string | null) => void
   toggleDeadline: (item: string) => void
+  setDeadline: (item: string | null) => void
   toggleResult: (code: number) => void
   setKeyword: (keyword: string) => void
   setCurrentPage: (page: number) => void
@@ -38,6 +39,7 @@ export const useListStore = create<ListState>((set) => ({
   setStatus: (item) => set({ selectedStatus: item, selectedResult: null, currentPage: 1 }),
   toggleDeadline: (item) =>
     set((s) => ({ selectedDeadline: toggle(s.selectedDeadline, item), currentPage: 1 })),
+  setDeadline: (item) => set({ selectedDeadline: item, currentPage: 1 }),
   toggleResult: (code) =>
     set((s) => ({ selectedResult: s.selectedResult === code ? null : code, selectedStatus: null, currentPage: 1 })),
   setKeyword: (keyword) => set({ keyword, currentPage: 1 }),