core: stdcm: optimize incremental conflict detection

[eckter]

Fix #9801
Helps with #10034 without entirely fixing it

Possible review by commit (though it's possible to just ignore the previous version and read the new one on its own):

1. Split "static" and "incremental" conflict detection classes (the uses and possible optimizations differ quite a lot)
2. Remove incremental routing conflict detection (wasn't used and brought lots of complexity, we can add it back later)
3. Use range sets / tree maps for zone uses instead of a list of requirements

I haven't run a proper benchmark as it requires a pretty specific setup (thousands of trains in a realistic timetable), but I do have some metrics:

• In the profiler, this section of the code goes from ~60% of execution time down to 2-5%
• On the slowest request I've logged (uncapped), execution time goes from 330s down to 190s. Still a timeout but not by much (180s threshold)

This PR also reduces code complexity by quite a lot, and may fix some of the "mismatch" crashes.

---

edit: hold on, the new version still takes up a lot of time when it timeout (a lot more than 2-5% execution time). On one massive request, the time we spend in the conflict detection methods goes from 71% to 45% execution time: it's much better but still quite a lot. edit2: partially fixed by #10126.

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[bougue-pe]

Thanks for this works, found the new code quite easy to read indeed 🙏
(some of my suggestions may tend to old code intricacy...)

Didn't review the old code and what might be missing from it.

As I understand it, we just don't check the routing requirements since STDCM v2, and this PR removes the check from v1. Which is fine by me (trusting you on a late non-incremental check for routing conflicts 🙈).

[Erashin]

Removing the routingRequirements + higherEntry really simplifies everything. Maybe we'll be able to do things more easily with this structure as well once/if we have to add the routing requirements back (it was really bloated with the previous way it was coded).
I'll let you deal with the other comments, but this looks pretty decent already.

[bougue-pe]

Improved perf and much clearer to me too, thanks for all this, really helps to dive in this part 🙏

[Erashin]

Gj!