Fix deadlock in fog detection logic and improved unit test

[RomanBapst]

Solved Problem

If the range finder detected fog for more than 1 second, the range finder could never be declared valid anymore due to a deadlock.

Fixes #{Github issue ID}

Solution

Remove condition which requires data to have been valid for the last second from the fog checks. This is to make sure that the fog detection logic can reset itself.

I also fixed the unit tests.

Changelog Entry

For release notes:

Feature/Bugfix XYZ
New parameter: XYZ_Z
Documentation: Need to clarify page ... / done, read docs.px4.io/...

Alternatives

We could also ...

Test coverage

• Unit/integration test: ...
• Simulation/hardware testing logs: https://review.px4.io/

Context

Related links, screenshot before/after, video

[github-actions]

🔎 FLASH Analysis

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Updated: 2025-02-07T13:51:27

[haumarco]

Should we not only check for fog-blockage when we know that the range data is otherwise good during the last second?
I didn't check for is_blocked and is_stuck directly since they have a hysteresis.

here