[Bug] cityhub goes into rapid constant blinking on button-press to power-off

[BertLindeman]

Describe the bug What is the problem? Button-press and keep to power-off sometimes ends with a rapid constant-blink situation. Need to take out the battery to repair.

To reproduce Steps to reproduce the behavior:

1. install CI-firmware ci-build-4515-v4.0.0b3-2-gf3f6ccbe on 2025-12-08 on a cityhub
2. Button press the cityhub to start
3. Button press and hold to power-off
4. When the hub starts blinking to indicate power-off, quickly release the button
5. If the hub keeps rapidly blinking, you need to remove the battery

Expected behavior What did you expect to happen instead? A simple power-off would be the expected action.

Screenshots There is a saying that a picture is worth a 1000 words. Screenshots really help to identify and solve problems.

Extra info Was trying to see if #2176 did re-occur. Could not reproduce, so fine. But out of ten power-off test the constant-blink situation occurred once. Next tests took ~40 attempts. This is very hard to reproduce, but seen twice in a few minutes.