Fix: Do not send vehicles towards incomplete PF nodes

YAPF could end up in a situation where it sets the best intermediate node
to a node whose construction is never finalized (i.e. it is never added to
the open list). The content of the node would be overwritten in the next
round, potentially sending the vehicle to an unwanted location.

Fix: Encountering two-way red signals could prune unrelated branches.

The intermediate node branch is now only pruned if the node is on the
path leading to the two-way red signal.

Remove: performance measurements in YAPF

YAPF was constantly measuring its performance, but only at
certain debug-levels this information was shown.

Now after years, I sincerely wonder if anyone still knows about this
feature and who still use it. Especially with the new framerate window,
this detailed performance is not as meaningful anymore as it once
was.

Remove: NO_DEBUG_MESSAGES was only read and setting it broke compilation (#6703)

Given any speed issue cannot be attributed to checking for _debug_NNN_level, removing this is a safe action

This fixes #6652.