Citrine Pokecenter, trade refactoring

I am tired of doing the Legendary wing event, so I'm populating Citrine City.

Some notes;
- I refactored the In-Game Trades to match their nicknames and re-distributed them.
- I swapped Fuschia's bench guy for the third unused one meant for the safe house, but I may outright restore these.
- I refactored the Pokecenter Hidden Objects to all use the same set - they're clones of each other, so this works out. This saves a TON of bytes and works fine.
- I placed the Harry trade for Kadabra/Alakazam in Citrine Pokecenter as it feels right for such a powerful Pokemon to be post-game.

data/maps/objects/CitrineCity.asm

@@ -4,6 +4,7 @@ CitrineCity_Object:
 	def_warp_events
 	warp_event  9, 27, CITRINE_ROCKET_HOUSE, 1
 	warp_event  9, 17, CITRINE_TRADEBACK_HOUSE, 1
+	warp_event 15, 17, CITRINE_POKECENTER, 1
 
 	def_bg_events