Revise some map scripts, mostly for getting items

engine/events/hidden_objects/pokecenter_pc.asm

@@ -3,7 +3,7 @@ OpenPokemonCenterPC:
 	cp SPRITE_FACING_UP
 	ret nz
 	call EnableAutoTextBoxDrawing
-	ld a, $1
+	ld a, TRUE
 	ld [wAutoTextBoxDrawingControl], a
 	tx_pre_jump PokemonCenterPCText
 

engine/events/oaks_aide.asm

@@ -25,22 +25,22 @@ OaksAideScript:
 	jr nc, .bagFull
 	ld hl, OaksAideGotItemText
 	call PrintText
-	ld a, $1
+	ld a, OAKS_AIDE_GOT_ITEM
 	jr .done
 .bagFull
 	ld hl, OaksAideNoRoomText
 	call PrintText
-	xor a
+	xor a ; OAKS_AIDE_BAG_FULL
 	jr .done
 .notEnoughOwnedMons
 	ld hl, OaksAideUhOhText
 	call PrintText
-	ld a, $80
+	ld a, OAKS_AIDE_NOT_ENOUGH_MONS
 	jr .done
 .choseNo
 	ld hl, OaksAideComeBackText
 	call PrintText
-	ld a, $ff
+	ld a, OAKS_AIDE_REFUSED
 .done
 	ldh [hOaksAideResult], a
 	ret

engine/slots/slot_machine.asm

@@ -1,6 +1,6 @@
 PromptUserToPlaySlots:
 	call SaveScreenTilesToBuffer2
-	ld a, BANK(DisplayTextIDInit)
+	ld a, BANK(DisplayTextIDInit) ; TRUE
 	ld [wAutoTextBoxDrawingControl], a
 	ld b, a
 	ld hl, DisplayTextIDInit