[C2] [L2Server/L2NPC] Extend SEE_CREATURE event for all creatures

[Master Toma]

There are special checks in C1, that NPC-NPC SEE_CREATURE event is disabled (in both, L2Server and L2NPC). To enable NPC-NPC SEE_CREATURE event, only check removal has to be done. Those events are used for NPC to NPC casts (e.g. from same clan), also to trigger aggro mobs on summons and pets.

After check removals AI has to be aligned:

    EventHandler SEE_CREATURE(creature)
    {
        if( creature.is_pc == 0 && IsInCategory(@summon_npc_group, creature.class_id) == 0 )
        {
            return;
        }
        //... old C1 code
    }

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