MuonR4 kickoff the hit validation modules

Hi everybody,

this MR kicksoff the developments of a MuonR4 validation chain on hit-level, starting with writing the simhits into a dedicated n-tuple. Hopefully, this will help us to improve the physics validation in a long-term perspective.

Tagging: @mbandier, @schaarsc, @juhofer, @rbianchi, @turra