Clean up bugs commented in the source code (#912)

Co-authored-by: Rangi <remy.oukaour+rangi42@gmail.com>

engine/battle/ai/items.asm

@@ -552,6 +552,7 @@ EnemyUsedMaxPotion:
 	jr FullRestoreContinue
 
 EnemyUsedFullRestore:
+; BUG: AI use of Full Heal does not cure confusion status (see docs/bugs_and_glitches.md)
 	call AI_HealStatus
 	ld a, FULL_RESTORE
 	ld [wCurEnemyItem], a
@@ -559,6 +560,7 @@ EnemyUsedFullRestore:
 	res SUBSTATUS_CONFUSED, [hl]
 	xor a
 	ld [wEnemyConfuseCount], a
+	; fallthrough
 
 FullRestoreContinue:
 	ld de, wCurHPAnimOldHP
@@ -725,6 +727,7 @@ EnemyUsedFullHealRed: ; unreferenced
 	jp PrintText_UsedItemOn_AND_AIUpdateHUD
 
 AI_HealStatus:
+; BUG: AI use of Full Heal or Full Restore does not cure Nightmare status (see docs/bugs_and_glitches.md)
 	ld a, [wCurOTMon]
 	ld hl, wOTPartyMon1Status
 	ld bc, PARTYMON_STRUCT_LENGTH
@@ -732,14 +735,6 @@ AI_HealStatus:
 	xor a
 	ld [hl], a
 	ld [wEnemyMonStatus], a
-	; Bug: this should reset SUBSTATUS_NIGHTMARE
-	; Uncomment the 2 lines below to fix
-	; ld hl, wEnemySubStatus1
-	; res SUBSTATUS_NIGHTMARE, [hl]
-	; Bug: this should reset SUBSTATUS_CONFUSED
-	; Uncomment the 2 lines below to fix
-	; ld hl, wEnemySubStatus3
-	; res SUBSTATUS_CONFUSED, [hl]
 	ld hl, wEnemySubStatus5
 	res SUBSTATUS_TOXIC, [hl]
 	ret