feat(task): inject uploaded documents into task materials and enable LAN host access

- backend: add Materials field to TaskRunRequestDTO and forward to ExecuteTask
- backend: add TestTaskStream_MaterialsInjection test case in taskstream_test.go
- web: serialize materials in buildTaskRequest and add unit test
- web: improve isSameMessage identity comparison in messageIdentity.ts
- web: configure host: '0.0.0.0' in vite.config.ts for LAN collaboration access

web/src/api/taskStream.test.ts

@@ -35,6 +35,21 @@ test('buildTaskRequest: omits optional fields when absent', () => {
   assert.equal('target_market' in req, false);
   assert.equal('user_id' in req, false);
   assert.equal('project_id' in req, false);
+  assert.equal('materials' in req, false);
+});
+
+test('buildTaskRequest: includes materials when provided and non-empty', () => {
+  const req = buildTaskRequest({
+    taskKey: 'intake',
+    projectName: 'P',
+    customerName: 'C',
+    deviceType: 'D',
+    materials: [
+      { filename: 'doc1.txt', content: 'b64content==' },
+    ],
+  });
+  assert.equal('materials' in req, true);
+  assert.deepEqual(req.materials, [{ filename: 'doc1.txt', content: 'b64content==' }]);
 });
 
 test('buildResumeRequest: adds work_dir on top of task request', () => {