feat: add weekly curriculum cover image upload and display

src/components/WeekCoverEditor.tsx

@@ -0,0 +1,54 @@
+import { useRef, useState } from 'react';
+import { ImagePlus, Loader2, Trash2 } from 'lucide-react';
+import { deleteCurriculumReference, uploadCurriculumReference, type CurriculumReference } from '../lib/curriculum';
+
+type Props = {
+  accessToken: string;
+  courseId: string;
+  week: number;
+  cover: CurriculumReference | null;
+  onChange: (cover: CurriculumReference | null) => void;
+};
+
+export function WeekCoverEditor({ accessToken, courseId, week, cover, onChange }: Props) {
+  const input = useRef<HTMLInputElement>(null);
+  const [busy, setBusy] = useState(false);
+  const [error, setError] = useState('');
+  async function save(file?: File) {
+    if (busy || (!file && !cover)) return;
+    if (file && (!['image/png', 'image/jpeg', 'image/webp'].includes(file.type) || file.size > 8 * 1024 * 1024)) {
+      setError('8MB 이하의 PNG, JPEG, WebP 이미지를 선택해주세요.');
+      return;
+    }
+    setBusy(true);
+    setError('');
+    try {
+      const result = file
+        ? await uploadCurriculumReference(accessToken, { courseId, week, file, kind: 'cover-image' })
+        : await deleteCurriculumReference(accessToken, cover!.id, courseId);
+      onChange(result.weeks.find((item) => item.week === week)?.detail.coverImage ?? null);
+    } catch (reason) {
+      setError(reason instanceof Error ? reason.message : '대표이미지를 저장하지 못했습니다.');
+    } finally { setBusy(false); }
+  }
+  return (
+    <section>
+      <div className="flex items-center justify-between gap-3">
+        <h3 className="text-[15px] font-black text-[#111827]">대표이미지</h3>
+        <div className="flex gap-2">
+          <button type="button" disabled={busy} onClick={() => input.current?.click()}
+            className="inline-flex h-8 items-center gap-1.5 rounded-md border border-[#d1d9e6] bg-white px-3 text-[12px] font-bold disabled:opacity-50">
+            {busy ? <Loader2 size={14} className="animate-spin" /> : <ImagePlus size={14} />}
+            {busy ? '저장 중' : cover ? '이미지 변경' : '이미지 업로드'}
+          </button>
+          {cover && <button type="button" title="대표이미지 삭제" aria-label="대표이미지 삭제" disabled={busy}
+            onClick={() => void save()} className="grid h-8 w-8 place-items-center rounded-md border border-[#d1d9e6] bg-white text-red-600 disabled:opacity-50"><Trash2 size={14} /></button>}
+        </div>
+      </div>
+      <input ref={input} type="file" accept="image/png,image/jpeg,image/webp" className="hidden"
+        onChange={(event) => { const file = event.target.files?.[0]; event.target.value = ''; if (file) void save(file); }} />
+      {cover && <img src={cover.downloadUrl} alt={`${week}주차 대표이미지`} className="mt-3 h-[240px] w-full rounded-md object-cover object-center" />}
+      {error && <p role="alert" className="mt-2 text-[13px] text-red-600">{error}</p>}
+    </section>
+  );
+}

src/lib/curriculum.ts

@@ -9,6 +9,7 @@ export type CurriculumWeek = {
   duration: string;
   github: string;
   detail: {
+    coverImage?: CurriculumReference | null;
     camera?: { url: string };
     overview: string;
     learningSteps?: Array<{
@@ -255,6 +256,7 @@ export async function uploadCurriculumReference(
     week: number;
     title?: string;
     file: File;
+    kind?: 'cover-image';
   },
 ): Promise<InstructorCurriculumResponse> {
   const formData = new FormData();
@@ -262,7 +264,7 @@ export async function uploadCurriculumReference(
   formData.set('courseId', input.courseId ?? '');
   formData.set('title', input.title?.trim() || input.file.name);
 
-  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum/weeks/${input.week}/references`, {
+  const response = await fetch(`${LMS_API_BASE_URL}/instructor/curriculum/weeks/${input.week}/${input.kind ?? 'references'}`, {
     method: 'POST',
     headers: {
       Authorization: `Bearer ${accessToken}`,

src/pages/curriculum/CurriculumPage.tsx

@@ -2,6 +2,7 @@ import { useEffect, useMemo, useRef, useState } from 'react';
 import { createPortal } from 'react-dom';
 import { CheckCircle2, CirclePlay, Clock3, FileCode2, FileText, Loader2, Map, Plus, RadioTower, Save, Target, Trash2, Upload, UsersRound, type LucideIcon } from 'lucide-react';
 import { ConfirmDialog } from '../../components/ConfirmDialog';
+import { WeekCoverEditor } from '../../components/WeekCoverEditor';
 import { PageHeader } from '../../components/PageHeader';
 import { useToast } from '../../components/ToastProvider';
 import { createInstructorCurriculumMap, deleteCurriculumReference, deleteInstructorCurriculumWeek, getInstructorCurriculum, updateInstructorCurriculum, uploadCurriculumExampleCode, uploadCurriculumReference, type CurriculumEnvironmentProfile, type CurriculumWeek, type InstructorCurriculumResponse } from '../../lib/curriculum';
@@ -106,6 +107,7 @@ function readEnvironmentModuleDockerImages(
 export function CurriculumPage({ session, selectedCourseId }: { session: AuthSession; selectedCourseId: string }) {
   const { showToast } = useToast();
   const [weeks, setWeeks] = useState<CurriculumWeek[]>([]);
+  const [coverOverrides, setCoverOverrides] = useState<Record<string, CurriculumWeek['detail']['coverImage']>>({});
   const [groups, setGroups] = useState<InstructorGroup[]>([]);
   const [selectedGroupId, setSelectedGroupId] = useState<string>('');
   const [activeWeek, setActiveWeek] = useState(1);
@@ -1398,6 +1400,11 @@ export function CurriculumPage({ session, selectedCourseId }: { session: AuthSes
                 )}
               </div>
             </section>
+            {selectedWeek && <WeekCoverEditor key={`${selectedCourseId}:${selectedWeek.week}`}
+              accessToken={session.accessToken} courseId={selectedCourseId} week={selectedWeek.week}
+              cover={coverOverrides[`${selectedCourseId}:${selectedWeek.week}`] !== undefined
+                ? coverOverrides[`${selectedCourseId}:${selectedWeek.week}`] ?? null : selectedWeek.detail.coverImage ?? null}
+              onChange={(cover) => setCoverOverrides((current) => ({ ...current, [`${selectedCourseId}:${selectedWeek.week}`]: cover }))} />}
             <label className="block">
               <h3 className="text-[15px] font-black text-[#111827]">제출 기준</h3>
               <textarea