-- time sync: Couple virtual time to wall clock

[KonradBkd]

Subject

Introduce wall clock coupling of virtual time. Accessible via participant configuration:

Experimental:
  TimeSynchronization:
    AnimationFactor: 1.0

Description

• Added a WallClockCoupling thread similar to the WatchDog thread that manages the time advances when due
• Prevent sending NextSimTask at other places than the WallClockCoupling thread if the coupling is active
• Improved performance for mixed system w/ wo/ time synchronization by not sending NextSimTask message to participants that don't use a TimeSyncService:
  • The timeSyncService is created by default with a lifecycle service, although it might be unused
  • Now, controllers can be created internally without performing the message subscriptions (preventing RegisterSilKitService)
  • For the TimeSyncService, the subscriptions are then performed when the user calls CreateTimeSyncService

Instructions for review / testing

• Review code changes
• Review changes to docs in configuration.rst and experimental-configuration.rst
• Try with any demo: Comment out sleeps in SimStepHandler, use adapted participant config with e.g.

Experimental:
  TimeSynchronization:
    AnimationFactor: 100.0

• Test is not run in the CI, run FTest_WallClockCoupling.cpp manually

Developer checklist (address before review)

• [x] Changelog.md updated
• [x] Documentation updated (public API changes only)
• [ ] Squash and merge → proper PR title