Fresh installation: Overlay not working due to NumPy 2.x / OpenCV incompatibility

[Empire4191]

Description:

On a fresh installation of Raspberry Pi OS Bookworm (32-bit, June 18 2026) and the latest AllSky version, the Overlay does not work. The Variable Manager is empty and no overlay fields (time, sunrise, text, etc.) are available.

The log shows:

AttributeError: _ARRAY_API not found
ImportError: numpy.core.multiarray failed to import

The cause is that NumPy 2.x is installed in the AllSky virtual environment while the installed OpenCV version is not compatible.

Workaround:

source ~/allsky/venv/bin/activate
pip uninstall numpy -y
pip install "numpy<2"

After downgrading NumPy, the Overlay and Variable Manager work immediately again.

I was able to reproduce this issue on two separate fresh installations.