[PWGJE] update the jet v2 in-plane and out-of-plane selection, fix several issue

[YubiaoWang]

1. Fixed event-plane validity checks (changed || to &&)
2. Wrapped raw angle differences into the (0 \sim 2\pi) interval
3. Fixed random cone RNG seeding (removed repeated SetSeed(0) in init{})
4. Resolved memory leak in if (temppara[0] == 0) (added a histogram and replaced return;)
5. Moved fitting plot and function cleanup inside the loop in processSigmaPtAreaSubMCP
6. Removed extra occupancy and event selection in processInOutJetV2MCD
7. Added skipMBGapEvents in jetderiveddatautilities::selectCollision()
8. Removed old function fitFncMCP()
9. Fixed inconsistency in leading jet usage: fillLeadingJetQA assumes the highest-pT jet,
   while RC veto used jets.iteratorAt(0). Now both use the same leading jet definition

[github-actions]

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