Core/MovementGenerator: Add more details to asserts

Include movespline in Unit::GetDebugInfo() and the Player owner in FlightPathMovementGenerator::DoEventIfAny() assert

(cherry picked from commit 560b7e33974904938f3f85a2f78c0850df2f9333)

src/server/game/Entities/Unit/Unit.cpp

@@ -13178,6 +13178,7 @@ std::string Unit::GetDebugInfo() const
         << std::boolalpha
         << "IsAIEnabled: " << IsAIEnabled() << " DeathState: " << std::to_string(getDeathState())
         << " UnitMovementFlags: " << GetUnitMovementFlags() << " ExtraUnitMovementFlags: " << GetExtraUnitMovementFlags()
-        << " Class: " << std::to_string(GetClass());
+        << " Class: " << std::to_string(GetClass()) << "\n"
+        << " " << (movespline ? movespline->ToString() : "Movespline: <none>");
     return sstr.str();
 }

src/server/game/Movement/MovementGenerators/FlightPathMovementGenerator.cpp

@@ -244,7 +244,7 @@ void FlightPathMovementGenerator::SetCurrentNodeAfterTeleport()
 
 void FlightPathMovementGenerator::DoEventIfAny(Player* owner, TaxiPathNodeEntry const* node, bool departure)
 {
-    ASSERT(node);
+    ASSERT(node, owner->GetDebugInfo().c_str());
 
     if (uint32 eventid = departure ? node->DepartureEventID : node->ArrivalEventID)
     {