We persist PVs (RecVertex) and their tracks (v1 tracks), but refitting them is currently only possible with the PrKalman or TrackMasterFitter. This breaks the reproducibility of what happens in HLT2, which uses tracks fitted with the VeloKalman. The functions in the VeloKalmanHelpers are unfortunately specific to the SoA containrs.
This MR adds a VeloKalmanV1 algorithm that is able to fit v1 tracks.
Closes #587 (closed)
NOTE: Once merged to master, a cherrypick MR should be opened back porting this to 2024-patches. See discussion below.