fix: start.sh 增加 cv2 空壳兜底——pip 24.0 解压 abi3 wheel 偶发丢根文件（cv2.abi3.so/__init__.py 缺失致 OCR 全挂），检测后 pip download + zipfile 手动解压（幂等）

scripts/start.sh

@@ -16,4 +16,34 @@ fi
 pip uninstall -y -q opencv-python 2>/dev/null || true
 pip install -q -i https://pypi.tuna.tsinghua.edu.cn/simple "opencv-python-headless>=4.8,<5"  # 5.x wheel 无 cv2 模块，锁定 4.x
 
+# pip 24.0 解压 abi3 wheel 偶发丢根文件（4.14.0.94 实测 site-packages/cv2 只剩子目录，
+# cv2.abi3.so / __init__.py 缺失 → import cv2 成空壳，OCR 全挂）→ 空壳检测 + wheel 手动解压兜底（幂等）
+python3 - <<'PY'
+import glob, os, shutil, site, subprocess, sys, zipfile
+
+def cv2_ok():
+    try:
+        import cv2
+        return hasattr(cv2, "__version__") and cv2.__file__ is not None
+    except Exception:
+        return False
+
+if cv2_ok():
+    sys.exit(0)
+print("cv2 空壳，wheel 手动解压修复...")
+r = subprocess.run(["pip", "download", "--no-deps", "-q",
+                    "-i", "https://pypi.tuna.tsinghua.edu.cn/simple",
+                    "-d", "/tmp/ocv", "opencv-python-headless>=4.8,<5"], capture_output=True)
+if r.returncode != 0:
+    sys.exit(1)
+w = sorted(glob.glob("/tmp/ocv/opencv_python_headless*.whl"))[-1]
+with zipfile.ZipFile(w) as z:
+    z.extractall("/tmp/ocv")
+dst = os.path.join(site.getsitepackages()[0], "cv2")
+shutil.rmtree(dst, ignore_errors=True)
+shutil.copytree("/tmp/ocv/cv2", dst)
+import cv2
+print(f"cv2 {cv2.__version__} 手动解压修复完成")
+PY
+
 exec python -u web_server.py