ITS: track memory allocations + graceful of exceeding limit #14326
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based on #14312 (will rebase if merged)
the pr aims to allow to stop the occasional exponential growth of buffers by using a custom allocator which throws an exception if the configurable memory limit is exceeded by the request. the algorithm then gracefully (before allocating any memory) drops the time slice.
for this to work a switch to tbb had to be done since in omp the exception thrown has to be handled by the throwing thread and is not propagated to the master thread. tbb guarantees this + cancellation of all parallel work.
Validation of getting the same output after modifications:

no particular gain/loss for the vertexing:

a >50% gain in findRoads due an optimisation switching away from an atomic variable under heavy contention:

before the change:

after the change:

P.S. Also sorry for these insanely big PRs, this is not nice for reviewers or to other people that work on the code basis.