[Bots] Add attack flag when told to attack (#4490)

This adds a flag to mobs that are told to attack by their owner to prevent unintended attacks.

Previously, if you were to send your bots to attack a target and then switch targets: before casters land their spell or if melee (especially anyone with pets)  hasn't engaged before the target switch, they could switch to your new target and attack.

This adds a flag upon attack and bots will only attack flagged targets.

zone/mob.h

@@ -205,6 +205,9 @@ public:
 	Timer                             mob_close_scan_timer;
 	Timer                             mob_check_moving_timer;
 
+	// Bot attack flag
+	Timer bot_attack_flag_timer;
+
 	//Somewhat sorted: needs documenting!
 
 	//Attack
@@ -1102,6 +1105,11 @@ public:
 	bool invulnerable;
 	bool qglobal;
 
+	inline std::vector<uint32> GetBotAttackFlags() { return bot_attack_flags; }
+	inline void SetBotAttackFlag(uint32 value) { bot_attack_flags.push_back(value); }
+	inline void ClearBotAttackFlags() { bot_attack_flags.clear(); }
+	bool HasBotAttackFlag(Mob* tar);
+
 	virtual void SetAttackTimer();
 	inline void SetInvul(bool invul) { invulnerable=invul; }
 	inline bool GetInvul(void) { return invulnerable; }
@@ -1863,6 +1871,9 @@ protected:
 	bool pet_owner_npc;    // Flags pets as belonging to an NPC
 	uint32 pet_targetlock_id;
 
+	//bot attack flags
+	std::vector<uint32> bot_attack_flags;
+
 	glm::vec3 m_TargetRing;
 
 	GravityBehavior flymode;