feat(exam): S4-11 marking flow, results table, CSV, ResultsWidget

- /exam-marker/:batchId/mark — ExamMarkingPage: student queue, per-part mark entry, upsert marks
- /exam-marker/:batchId/results — ExamResultsPage: results table with absent rows, CSV download
- ResultsWidget on ClassDetailPage: last batch summary, class average, absent count, batch creation
- New types: MarkingBatch, StudentSubmission, BatchQueueResponse, BatchResultsResponse, MarkUpsertPayload
- New repo methods: createBatch, listBatches, getBatchQueue, getBatchResults, getBatchCsv, upsertMark

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

src/services/exam/examRepository.ts

@@ -11,12 +11,17 @@ import { API_BASE } from '../../config/apiConfig';
 import { logger } from '../../debugConfig';
 import { supabase } from '../../supabaseClient';
 import type {
+  BatchQueueResponse,
+  BatchResultsResponse,
+  CreateBatchPayload,
   CreateTemplatePayload,
   ExamBoundary,
   ExamQuestion,
   ExamResponseArea,
   ExamTemplate,
   ExamTemplateDetail,
+  MarkingBatch,
+  MarkUpsertPayload,
   Neo4jSyncResult,
   PatchQuestionPayload,
   SpecPoint,
@@ -209,6 +214,48 @@ export const examRepository = {
     const res = await axios.post<Neo4jSyncResult>(`${EXAM_BASE}/templates/${templateId}/neo4j-sync`, {}, { headers });
     return res.data;
   },
+
+  async createBatch(payload: CreateBatchPayload): Promise<MarkingBatch> {
+    const headers = await authHeaders();
+    const res = await axios.post<MarkingBatch>(`${EXAM_BASE}/batches`, payload, { headers });
+    return res.data;
+  },
+
+  async listBatches(params: { includeArchived?: boolean; templateId?: string } = {}): Promise<MarkingBatch[]> {
+    const headers = await authHeaders();
+    const res = await axios.get<{ batches: MarkingBatch[] }>(`${EXAM_BASE}/batches`, {
+      headers,
+      params: {
+        include_archived: params.includeArchived ?? false,
+        template_id: params.templateId,
+      },
+    });
+    return res.data.batches ?? [];
+  },
+
+  async getBatchQueue(batchId: string): Promise<BatchQueueResponse> {
+    const headers = await authHeaders();
+    const res = await axios.get<BatchQueueResponse>(`${EXAM_BASE}/batches/${batchId}/queue`, { headers });
+    return res.data;
+  },
+
+  async getBatchResults(batchId: string): Promise<BatchResultsResponse> {
+    const headers = await authHeaders();
+    const res = await axios.get<BatchResultsResponse>(`${EXAM_BASE}/batches/${batchId}/results`, { headers });
+    return res.data;
+  },
+
+  async getBatchCsv(batchId: string): Promise<string> {
+    const headers = await authHeaders();
+    const res = await axios.get<string>(`${EXAM_BASE}/batches/${batchId}/csv`, { headers, responseType: 'text' });
+    return res.data;
+  },
+
+  async upsertMark(markId: string, payload: MarkUpsertPayload): Promise<unknown> {
+    const headers = await authHeaders();
+    const res = await axios.put(`${EXAM_BASE}/marks/${markId}`, payload, { headers });
+    return res.data;
+  },
 };
 
 export default examRepository;