Summary

I used the ~$2 Aliexpress zigbee door sensor, modify the enclosure to fit 12mm hole in the door made using cheap router.
The STLs include jig for my router.
I used 12mm 2-flute bit to carve the opening in single pass.
I left ~1-1.5cm bigger opening for easy sensor removal when replacing batteries.
The upper frame needs a 5mm hole for cube neodymium magnet (4x4x4mm).