cbmreco: Integrate TOF Hitfinder.

Integrate TOF Hitfinder:

• Changed return type to PartitionedVector
• Renamed TofCluster to tof::Hit
• Pass tof Hits to tracking

@d.smith: Didn't touch the algorithm itself. But made some other changes. In particular changed the return type of the Hitfinder to easier integrate with tracking. There were also some Digis with weird RPCs. Those crashed the DigiCalibration. I added some checks to turn this into monitoring errors instead.

@s.zharko: Makes tof::Hits available to tracking. I tried to integrate into the tracker interface. It works in the sense that it compiles and doesn't crash. But doesn't find any tracks yet. Would appreciate if you could have a short look at my changes there before merging. Also there is now PartitionedSpan. Relates to PartitionedVector like std::span relates to std::vector and should be preffered for inputs. Makes things a bit easier.