Fix weapon switching, scale, add Q key bind

- Fixed weapon switching: player.gd now uses weapon_next/weapon_prev/slot actions
  (was checking for nonexistent 'weapon_toggle')
- Added Q key to weapon_next input action
- Reduced weapon scale from 0.3 to 0.07-0.08 (was still 3x too large)

assets/kenney-fps/objects/player.gd

@@ -227,11 +227,22 @@ func action_shoot():
 # Toggle between available weapons (listed in 'weapons')
 
 func action_weapon_toggle():
-	if Input.is_action_just_pressed("weapon_toggle"):
+	if Input.is_action_just_pressed("weapon_next"):
 		weapon_index = wrap(weapon_index + 1, 0, weapons.size())
 		initiate_change_weapon(weapon_index)
-		
 		Audio.play("assets/kenney-fps/sounds/weapon_change.ogg")
+	
+	if Input.is_action_just_pressed("weapon_prev"):
+		weapon_index = wrap(weapon_index - 1, 0, weapons.size())
+		initiate_change_weapon(weapon_index)
+		Audio.play("assets/kenney-fps/sounds/weapon_change.ogg")
+	
+	for i in range(4):
+		if Input.is_action_just_pressed("weapon_slot_" + str(i + 1)):
+			if i < weapons.size():
+				weapon_index = i
+				initiate_change_weapon(weapon_index)
+				Audio.play("assets/kenney-fps/sounds/weapon_change.ogg")
 
 # Initiates the weapon changing animation (tween)