Parallel Optimization

[samf25]

I made a number of changes to the algorithms in k4ActsTracking.

1. I improved the TruthTracking alg. Previously, it wasn't actually making use of its maps' runtime speed ups. I also used tbb's threading for the beefy for loop. This took the runtime (with BIB) from ~1000s to 0.5141s.
2. I used stable sort and memory reserving instead of the insertion method in the DuplicateRemoval to decrease runtime (I think this is $N^2 \rightarrow N\log N$).
3. I parallelized the CKFTrackingAlg's bottle neck loops (hit loop and seeding loop). This brings the runtime under control $\left(\frac{1}{n_{Threads}}\right)$ without increasing the memory demands (see plot).

[samf25]

The steering files for these new, parallel algs can be found here.
These steering files also use the thread-safe version of k4GaudiPandora

[madbaron]

Hi @samf25,

we've merged the PR with the previous set of updates into the key4hep/main.
When you have a moment, could you take a look at resolving the conflicts here?

We'll then merge this into our main, and start the PR to propagate the changes upstream.
Once we are done with this, I think we'll be able to close our fork, so any additional updates should target https://github.com/key4hep/k4ActsTracking directly.