perf: CKF measurement selector runs after track state creation

https://github.com/acts-project/acts/blob/4935604fa3c6ebae23467312684800a78e722c0b/Core/include/Acts/TrackFinding/CombinatorialKalmanFilter.hpp#L588-L591

After Acts-Athena track finding performance discussions I wondered if this might be one of the spots in our CKF where we loose CPU. For surfaces with tons of clusters we would create track states for each of them and only select the cluster afterwards.

I suppose this is done to get the calibration into place and prepare everything for the selection but I wonder if this is a reasonable overhead.

Apart from that we wondered if the calibration is strictly necessary for the selection or if we could have a loose cut without calibration and then a hard cut with calibration.

Start at Core/include/Acts/TrackFinding/CombinatorialKalmanFilter.hpp#L588-L591 and trace the CKF measurement-selection and track-state-creation flow. Check the relevant profiling or performance measurements, then determine whether selection can move earlier and whether calibration is required for each cut. Done means an agreed, measured approach rather than only a code change.

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