fix(teacher): 改善只读工具分页与读取预算

tests/unit/coding-teacher-cloud.test.ts

@@ -127,6 +127,37 @@ it('waits for the interrupted parent cleanup and resubmits the same three read r
   expect(paths.some(item => item.endsWith('/cancel'))).toBe(false);
 });
 
+it('returns the complete batch within the byte budget and lets the cloud finish with available evidence', async () => {
+  const f = await fixture();
+  await writeFile(path.join(f.access.projectPath, 'src/game.ts'), '源码🙂'.repeat(20000));
+  const results: { status: string; content: string }[] = [];
+  const transport: TeacherCloudTransport = {
+    events: vi.fn(),
+    json: vi.fn(async (url, body) => {
+      if (url === '/questions') return { request_id: 'question', run_id: 'one' };
+      if (url.endsWith('/tool-results')) {
+        results.push(...(body as { results: typeof results }).results);
+        return { run_id: 'done' };
+      }
+      if (url === '/runs/done') return { status: 'completed', output: '已检查的范围和待补充资料。' };
+      return { status: 'interrupted', interrupt: {
+        source: 'client_read_tools', context_id: requestId,
+        calls: Array.from({ length: 10 }, (_, i) => ({ tool_call_id: 'file-' + i, name: 'read_project_file',
+          arguments: { path: 'src/game.ts', start_column: 1 + i * 3000 } })),
+      } };
+    }),
+  };
+  const text = vi.fn();
+  await prepareCloudTeacher(f.account, f.topic, requestId, f.access, f.progress, f.saveRequest, transport)
+    .run([{ role: 'user', content: '检查' }], new AbortController().signal, text);
+  expect(results).toHaveLength(10);
+  const bytes = results.filter(item => item.status === 'success').reduce((sum, item) => sum + Buffer.byteLength(item.content), 0);
+  expect(bytes).toBeLessThanOrEqual(65536);
+  expect(bytes).toBeGreaterThan(65024);
+  expect(results.at(-1)).toMatchObject({ status: 'error', content: expect.stringContaining('budget exhausted') });
+  expect(text).toHaveBeenCalledWith('已检查的范围和待补充资料。');
+});
+
 it.each([
   { ...cleanupBusy, active_run_id: 'other-run' },
   { ...cleanupBusy, active_run_status: 'running' },
@@ -190,7 +221,7 @@ async function submitCompiledContext(
   await model.run(compiled.messages, new AbortController().signal, vi.fn());
   const body = vi.mocked(transport.json).mock.calls.find(([url]) => url === '/questions')?.[1] as {
     query: string;
-    local_context: { id: string; scope: { project_id: string; source_session_id: string }; tools: string[] };
+    local_context: { id: string; read_protocol: number; scope: { project_id: string; source_session_id: string }; tools: string[] };
   };
   expect(JSON.parse(body.query)).toEqual({ messages: compiled.messages });
   expect(estimateTeacherTokens(compiled.messages)).toBeLessThanOrEqual(model.inputLimit);
@@ -211,6 +242,7 @@ it('submits only the published persona, source evidence and current question in
   expect(compiled.messages[0].content).toContain('你可以通过只读工具');
   expect(compiled.messages[1].content).toContain(f.access.source.messages[0].text);
   expect(compiled.messages[2].content).toContain('当前问题：\n下一步怎么想？');
+  expect(body.local_context.read_protocol).toBe(2);
   expect(body.local_context.tools).toEqual(['list_project_files', 'read_project_file', 'read_conversation']);
 });
 
@@ -512,7 +544,7 @@ it.each(['方法老师', '朋友', '代码顾问'])('returns all three local rea
         expect.objectContaining({
           tool_call_id: 'chat',
           status: 'success',
-          content: expect.stringContaining('2: 调整重力'),
+          content: expect.stringContaining('调整重力'),
         }),
       ],
     },
@@ -522,7 +554,7 @@ it.each(['方法老师', '朋友', '代码顾问'])('returns all three local rea
   expect(f.progress).toHaveBeenCalledWith('正在读取项目与会话…');
 });
 
-it.each([false, true])('finishes six batches and rejects a seventh as a read limit (extra batch: %s)', async extraBatch => {
+it.each([false, true])('finishes twelve batches and rejects a thirteenth as a read limit (extra batch: %s)', async extraBatch => {
   const f = await fixture();
   const returned: unknown[] = [];
   const transport: TeacherCloudTransport = {
@@ -534,7 +566,7 @@ it.each([false, true])('finishes six batches and rejects a seventh as a read lim
         returned.push(body);
         return { run_id: `run-${returned.length}` };
       }
-      if (!extraBatch && returned.length === 6) return { status: 'completed', output: '已根据六批资料完成检查。' };
+      if (!extraBatch && returned.length === 12) return { status: 'completed', output: '已根据十二批资料完成检查。' };
       return { status: 'interrupted', interrupt: {
         source: 'client_read_tools', context_id: requestId,
         calls: [{ tool_call_id: `read-${returned.length}`, name: 'read_project_file', arguments: { path: 'src/game.ts' } }],
@@ -549,10 +581,10 @@ it.each([false, true])('finishes six batches and rejects a seventh as a read lim
     expect(transport.json).toHaveBeenCalledWith('/questions/' + requestId + '/cancel', {}, expect.anything());
   } else {
     await result;
-    expect(text).toHaveBeenCalledWith('已根据六批资料完成检查。');
+    expect(text).toHaveBeenCalledWith('已根据十二批资料完成检查。');
     expect(transport.json).not.toHaveBeenCalledWith('/questions/' + requestId + '/cancel', expect.anything(), expect.anything());
   }
-  expect(returned).toHaveLength(6);
+  expect(returned).toHaveLength(12);
 });
 
 it.each([