Fix boss planet landing controls

tests/_boss_approach_preview.gd

@@ -21,5 +21,5 @@ func _ready() -> void:
 	var surface: Node = load("res://surface/PlanetSurface.tscn").instantiate()
 	add_child(surface)
 	surface.get_node("FadeOverlay/FadeRect").visible = false
-	# Four screenshot frames are nowhere near enough for the automatic
-	# approach to cover 950 world units, so the signal remains off-screen.
+	# Four screenshot frames leave the fleet at its landing point, so the
+	# signal remains off-screen until the player chooses to follow it.