Remove all code from main.asm (some labeled INCBINs, like out-of-context graphics, are still present)

engine/routines/ stores isolated out-of-context routines as individual files. It might be preferable later to append them to their related engine/ files in unique little SECTIONs, relying on the linkerscript to place them appropriately; or some other organization method. In the meantime, they're now easily findable apart from main.asm's other content.

engine/routines/knowsmove.asm

@@ -0,0 +1,25 @@
+KnowsMove: ; f9ea
+	ld a, MON_MOVES
+	call GetPartyParamLocation
+	ld a, [wPutativeTMHMMove]
+	ld b, a
+	ld c, NUM_MOVES
+.loop
+	ld a, [hli]
+	cp b
+	jr z, .knows_move
+	dec c
+	jr nz, .loop
+	and a
+	ret
+
+.knows_move
+	ld hl, .Text_knows
+	call PrintText
+	scf
+	ret
+
+.Text_knows: ; 0xfa06
+	; knows @ .
+	text_jump UnknownText_0x1c5ea8
+	db "@"