Rename MON_ID to MON_OT_ID (#1114)

* Rename MON_ID to MON_TRAINER_ID

The constant name MON_ID implies it relates to the ID number of the
Pokémon itself. However, it actually refers to the Trainer ID number of
the Pokémon's Original Trainer. Renaming it to MON_TRAINER_ID makes it
substantially more clear what its purpose is.

The original definition of MON_ID is preserved in macros/legacy.asm

* Remove MON_ID from macros/legacy.asm

Co-authored-by: Sylvie <35663410+Rangi42@users.noreply.github.com>

* Apply rename to missed file

* Rename to `MON_OT_ID`

---------

Co-authored-by: SnorlaxMonster <snorlaxmonster@users.noreply.github.com>
Co-authored-by: Sylvie <35663410+Rangi42@users.noreply.github.com>
Co-authored-by: vulcandth <vulcandth@gmail.com>

engine/events/daycare.asm

@@ -491,7 +491,7 @@ DayCare_GiveEgg:
 	call AddNTimes
 	ld b, h
 	ld c, l
-	ld hl, MON_ID + 1
+	ld hl, MON_OT_ID + 1
 	add hl, bc
 	push hl
 	ld hl, MON_MAXHP

engine/events/halloffame.asm

@@ -172,7 +172,7 @@ GetHallOfFameParty:
 	ld [de], a
 	inc de
 
-	ld hl, MON_ID
+	ld hl, MON_OT_ID
 	add hl, bc
 	ld a, [hli]
 	ld [de], a

engine/events/lucky_number.asm

@@ -149,7 +149,7 @@ CheckForLuckyNumberWinners:
 .done
 	pop hl
 	push hl
-	ld de, MON_SPECIES - MON_ID
+	ld de, MON_SPECIES - MON_OT_ID
 	add hl, de
 	ld a, [hl]
 	pop hl

engine/events/magikarp.asm

@@ -11,7 +11,7 @@ CheckMagikarpLength:
 	cp MAGIKARP
 	jr nz, .not_magikarp
 
-	; Now let's compute its length based on its DVs and ID.
+	; Now let's compute its length based on its DVs and Trainer ID.
 	ld a, [wCurPartyMon]
 	ld hl, wPartyMon1Species
 	ld bc, PARTYMON_STRUCT_LENGTH
@@ -22,7 +22,7 @@ CheckMagikarpLength:
 	ld d, h
 	ld e, l
 	pop hl
-	ld bc, MON_ID
+	ld bc, MON_OT_ID
 	add hl, bc
 	ld b, h
 	ld c, l

engine/events/poke_seer.asm

@@ -107,7 +107,7 @@ ReadCaughtData:
 	ld a, SEERACTION_TRADED
 	ld [wSeerAction], a
 
-	ld a, MON_ID
+	ld a, MON_OT_ID
 	call GetPartyParamLocation
 	ld a, [wPlayerID]
 	cp [hl]