Notify monsters that summon appears

[nekiro]

Fix #2235

[WibbenZ]

Haven't tested it, but if you ask me it would be better to add this to C++ since we (and other datapacks) call the x:addSummon() / setMaster functions in other scripts.

[nekiro]

@WibbenZ then we should add it to addSummon method (its in lua)

[WibbenZ]

My mistake and in that case, yes we should add it there.
In these cases it's better to fix it at the source of a function rather than adding small fixes in all the codes we have(not to mention backwards compatibility).

If the rest disagrees with me you would have to fix it in these cases aswell: https://github.com/otland/forgottenserver/search?q=addSummon&unscoped_q=addSummon

[Leo32onGIT]

The only situations that trigger this, is when users on GOD characters are summoning monsters and trying to mess with players.

If you're doing that, who cares if monster are idle or 'dance' near you, plus it means you've already messed with groups.xml - so maybe this is appropriate?

#2848 (comment)

[nekiro]

@Leo32onGIT it was done like that before anyway (when was in sources), so that should be there imo