fix(Core/Entities): Knock back players if they are not under client control. (#26540)

Co-authored-by: Claude <claude@users.noreply.github.com>
Co-authored-by: sogladev <sogladev@gmail.com>

src/server/game/Movement/MotionMaster.cpp

@@ -620,7 +620,7 @@ void MotionMaster::MoveTakeoff(uint32 id, float x, float y, float z, float speed
 void MotionMaster::MoveKnockbackFrom(float srcX, float srcY, float speedXY, float speedZ)
 {
     //this function may make players fall below map
-    if (_owner->IsPlayer())
+    if (_owner->IsPlayer() && _owner->IsClientControlled())
         return;
 
     if (speedXY <= 0.1f)
@@ -640,6 +640,15 @@ void MotionMaster::MoveKnockbackFrom(float srcX, float srcY, float speedXY, floa
     init.SetOrientationFixed(true);
     init.SetVelocity(speedXY);
 
+    // Do not mutate an active fleeing/confused movement generator,
+    // doing so breaks the movement upon landing from the knockback
+    MovementGeneratorType slotType = GetMotionSlotType(MOTION_SLOT_CONTROLLED);
+    if (slotType == FLEEING_MOTION_TYPE || slotType == CONFUSED_MOTION_TYPE)
+    {
+        init.Launch();
+        return;
+    }
+
     Mutate(new EffectMovementGenerator(init, 0), MOTION_SLOT_CONTROLLED);
 }