Fill in SBND Data for raw::Trigger , DetectorTimings.h, detinfo::DetectorClocksService and DetectorClocks products

[VCLanNguyen]

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• bug report
• feature request

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Expected Behavior

SBND is currently not filling in any LArSoft products regarding timing information.

Current Behavior

Possible Solution (optional)

How to reproduce

[PetrilloAtWork]

The protocol includes:

• raw::Trigger with beam gate time and trigger time in microseconds, and with bits whose meaning is user-defined (ICARUS encodes the beam in there);
• sim::BeamGateInfo, originally for simulated samples but having it in data allows more general code; it is the only place where the beam gate duration is stored in LArSoft;
• raw::ExternalTrigger with the trigger timestamp (although I am not sure this is part of LArSoft protocol).

In addition, ICARUS fills sbn::ExtraTriggerInfo, which can be extended to add SBND-specific information if needed.