Mystery Box bugfixes and improvements

- Meltan is now loaded in engine/battle/wild_encounters.asm, allowing its level to be fixed at 5 and avoiding various glitches. This also fixed the "running from Meltan ends the Mystery Box game" bug.
- Candy Jar now gives a message when it's full, more transparent to the player.
- Fixed a bug where the increment text wouldn't load properly, it was very silly.

data/text/text_3.asm

@@ -328,3 +328,8 @@ _TradeCenterText1::
 _ColosseumText1::
 	text "!"
 	done
+
+_MeltanFullJar::
+	text "The CANDY JAR"
+	line "is full!"
+	prompt

engine/battle/core.asm

@@ -854,16 +854,16 @@ FaintEnemyPokemon:
 	; Increment the Candy Jar count.
 	ld a, [wCandyJarCount] ; Grab the jar.
 	cp 40 ; Do we have 40?
-	jr z, .skip ; If yes, no more candies.
+	jr z, .skipFilling1 ; If yes, no more candies.
 	inc a ; Increment candy count.
 	ld [wCandyJarCount], a ; Store candy count.
 	
-	; For engine\overworld\clear_variables.asm
-	; Needed so the Mystery Box effect isn't cleared upon leaving battle.
-	ld a, $01
-	ld [wDontSwitchOffMysteryBoxYet], a
-	
-	ld hl, _MeltanIncrement ; Load text to show it's going up.
+.skipFilling1
+	ld hl, MeltanFullJar ; Special message for when the jar is full
+	cp 40
+	jr z, .skipFilling2
+	ld hl, MeltanIncrement ; Load text to show it's going up.
+.skipFilling2
 	call PrintText ; Yep text.
 	call PrintEmptyString ; vs text likes this.
 .skip
@@ -6262,29 +6262,8 @@ LoadEnemyMonData:
 	cp LINK_STATE_BATTLING
 	jp z, LoadEnemyMonFromParty
 	
-	; Mystery Box functionality.
-	; First, we need to check if it's a trainer battle, or everyone will use Meltan.
-	ld a, [wIsInBattle]
-	cp $2 ; is it a trainer battle?
-	jr z, .skip ; If so, skip.
-	
-	; Upon initiating a battle, if not a trainer battle, check if the Mystery Box has been activated.
-	; ~50% of the time, Meltan will replace what you encounter.
-	ld a, [wMysteryBoxActive] ; Load the box.
-	cp $01 ; Check if it's active.
-	jr nz, .skip ; If not, load a normal Pokemon. I know this looks sort of weird, it's just how it panned out.
-	
-	; This didn't work for some reason. It seems unnecessary, anyway...
-	;call Random
-	;and a
-	;cp 128 ; Compare Random (a) with 128 (b).
-	;jr z, .cont ; If not within range, normal Pokemon appears. 50% chance.
-	
-	ld a, MELTAN ; Meltan is loaded...
-	ld [wEnemyMonSpecies2], a ; Here!
-	ld [wcf91], a
-
-.skip ; Standard loading.
+	; New Meltan encounter code in engine/battle/wild_encounters.asm
+	; It's way less buggy and just works better
 	ld a, [wEnemyMonSpecies2]
 	ld [wEnemyMonSpecies], a
 	ld [wd0b5], a
@@ -7269,3 +7248,11 @@ VermilionBeautyCheck:
 	ld [wBeautyCounter], a ; and get the FUCK out of my office!!!
 .skipCounting
 	ret
+
+MeltanIncrement:
+	text_far _MeltanIncrement
+	text_end
+
+MeltanFullJar:
+	text_far _MeltanFullJar
+	text_end

engine/battle/wild_encounters.asm

@@ -20,7 +20,7 @@ TryDoWildEncounter:
 	and a
 	jr z, .next
 	dec a
-	jr z, .lastRepelStep
+	jp z, .lastRepelStep
 	ld [wRepelRemainingSteps], a
 .next
 ; determine if wild pokemon can appear in the half-block we're standing in
@@ -53,10 +53,10 @@ TryDoWildEncounter:
 ; ...as long as it's not Viridian Forest or Safari Zone.
 	ld a, [wCurMap]
 	cp FIRST_INDOOR_MAP ; is this an indoor map?
-	jr c, .CantEncounter2
+	jp c, .CantEncounter2
 	ld a, [wCurMapTileset]
 	cp FOREST ; Viridian Forest/Safari Zone
-	jr z, .CantEncounter2
+	jp z, .CantEncounter2
 	ld a, [wGrassRate]
 .CanEncounter
 ; compare encounter chance with a random number to determine if there will be an encounter
@@ -84,6 +84,13 @@ TryDoWildEncounter:
 ; since the bottom right tile of a "left shore" half-block is $14 but the bottom left tile is not,
 ; "left shore" half-blocks (such as the one in the east coast of Cinnabar) load grass encounters.
 .gotWildEncounterType
+	; Meltan functionality.
+	; This used to be in engine/battle/core.asm.
+	; However, it was a bit buggy as the implementation was forced.
+	; So instead, we do this:
+	ld a, [wMysteryBoxActive] ; Load the box.
+	cp $01 ; Check if it's active.
+	jr z, .meltanEncounter ; If so, skip this.
 	ld b, 0
 	add hl, bc
 	ld a, [hli]
@@ -99,6 +106,25 @@ TryDoWildEncounter:
 	ld a, [wCurEnemyLVL]
 	cp b
 	jr c, .CantEncounter2 ; repel prevents encounters if the leading party mon's level is higher than the wild mon
+	jp .willEncounter
+.meltanEncounter ; needed this function as otherwise we really mess up regular processing for no reason
+	ld a, $01 
+	ld [wDontSwitchOffMysteryBoxYet], a ; Using this variable here accounts for running from Meltan.
+	ld b, 0
+	add hl, bc
+	ld a, 5
+	ld [wCurEnemyLVL], a
+	ld a, MELTAN
+	ld [wcf91], a
+	ld [wEnemyMonSpecies2], a
+	ld a, [wRepelRemainingSteps]
+	and a
+	jr z, .willEncounter
+	ld a, [wPartyMon1Level]
+	ld b, a
+	ld a, [wCurEnemyLVL]
+	cp b
+	jr c, .CantEncounter2
 	jr .willEncounter
 .lastRepelStep
 	ld [wRepelRemainingSteps], a