refactor: Align initial track param covariance

[andiwand]

Currently the initial track param covariance will depend on the chosen seeder. Truth smeared will use the configured sigmas to cook up a cov while to other seeder take a directly configured one.

Here I align the truth smeared to the others which also allows to experiment with the covariance separately from the smearing.

[codecov]

Codecov Report

Merging #2491 (27fc978) into main (4515f2c) will decrease coverage by 0.02%.
Report is 1 commits behind head on main.
The diff coverage is 26.66%.

@@            Coverage Diff             @@
##             main    #2491      +/-   ##
==========================================
- Coverage   49.82%   49.81%   -0.02%     
==========================================
  Files         466      466              
  Lines       26247    26248       +1     
  Branches    12050    12051       +1     
==========================================
- Hits        13078    13075       -3     
- Misses       4603     4606       +3     
- Partials     8566     8567       +1     

Files	Coverage Δ
.../include/Acts/TrackFinding/MeasurementSelector.hpp	32.81% <26.66%> (-5.29%)	⬇️

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[github-actions]

📊: Physics performance monitoring for 27fc978

Full contents

physmon summary

• ✅ CKF truth_smeared
• ✅ IVF truth_smeared
• ✅ AMVF truth_smeared
• ✅ Track Summary CKF truth_smeared
• ✅ Seeding truth_estimated
• ✅ CKF truth_estimated
• ✅ IVF truth_estimated
• ✅ AMVF truth_estimated
• ✅ Track Summary CKF truth_estimated
• ✅ Seeding seeded
• ✅ CKF seeded
• ✅ IVF seeded
• ✅ AMVF seeded
• ✅ AMVF (+grid seeder) seeded
• ✅ Track Summary CKF seeded
• ✅ Seeding orthogonal
• ✅ CKF orthogonal
• ✅ IVF orthogonal
• ✅ AMVF orthogonal
• ✅ Track Summary CKF orthogonal
• ✅ Ambisolver seeded
• ✅ Ambisolver orthogonal
• ✅ Seeding ttbar
• ✅ CKF ttbar
• ✅ Ambisolver
• ✅ AMVF ttbar
• ✅ AMVF (+grid seeder) ttbar
• ✅ Truth tracking (GSF)
• ✅ Truth tracking
• ✅ Particles inital fatras
• ✅ Particles final fatras
• ✅ Particles inital geant4
• ✅ Particles final geant4

[paulgessinger]

I like it. Either we restore the previous defaults, or we update the references.