Miscellaneous updates

- `PREDEFPAL_00` -> `PREDEFPAL_ROUTES` (observed from `LoadSGBLayout.GetMapPalsIndex.route`)
- `$0` -> `PLAYER` (standard person ID)
- Fix some whitespace formatting

engine/overworld/player_movement.asm

@@ -577,11 +577,14 @@ DoPlayerMovement::
 ; Standing
 	jr .update
 
-.d_down 	add hl, de
-.d_up   	add hl, de
-.d_left 	add hl, de
-.d_right	add hl, de
-
+.d_down
+	add hl, de
+.d_up
+	add hl, de
+.d_left
+	add hl, de
+.d_right
+	add hl, de
 .update
 	ld a, [hli]
 	ld [wWalkingDirection], a