feat(exam): render template PDFs behind setup canvas

src/services/exam/examRepository.ts

@@ -127,6 +127,15 @@ export const examRepository = {
     return res.data;
   },
 
+  async getTemplateSourcePdf(templateId: string): Promise<ArrayBuffer> {
+    const headers = await authHeaders();
+    const res = await axios.get<ArrayBuffer>(`${EXAM_BASE}/templates/${templateId}/source-pdf`, {
+      headers,
+      responseType: 'arraybuffer',
+    });
+    return res.data;
+  },
+
   async createTemplate(payload: CreateTemplatePayload): Promise<ExamTemplate> {
     const headers = await authHeaders();
     const res = await axios.post<ExamTemplate>(`${EXAM_BASE}/templates`, payload, { headers });