feat: add test tube pick task with custom assets and grasp annotations

- Add pick_test_tube task: USDC asset repackaging, grasp generation, task config
- Add tools: usdc_to_obj.py, repackage_test_tube.py, fix_test_tube_materials.py
- Add custom_task_guide.md: full Chinese documentation for creating custom tasks
- Add crawled InternDataEngine online docs (23 pages)
- Add grasp generation script (gen_tube_grasp.py) and pipeline config

configs/simbox/de_pick_test_tube.yaml

@@ -0,0 +1,31 @@
+name: simbox_pick_test_tube
+load_stage:
+  scene_loader:
+    type: env_loader
+    args:
+      workflow_type: SimBoxDualWorkFlow
+      cfg_path: workflows/simbox/core/configs/tasks/example/pick_test_tube.yaml
+      simulator:
+        physics_dt: 1/30
+        rendering_dt: 1/30
+        stage_units_in_meters: 1.0
+        headless: False                    # GUI mode for visual debugging first
+        renderer: "RayTracedLighting"
+        anti_aliasing: 0
+  layout_random_generator:
+    type: env_randomizer
+    args:
+      random_num: 1                        # Start with 1 sample for testing
+      strict_mode: true
+plan_stage:
+  seq_planner:
+    type: env_planner
+render_stage:
+  renderer:
+    type: env_renderer
+store_stage:
+  writer:
+    type: env_writer
+    args:
+      batch_async: true
+      output_dir: output/${name}/