Add gas bomber skill-shot vessel

VesselDefinition.gd

@@ -5,6 +5,7 @@ extends Resource
 @export var display_name: String
 @export_multiline var description: String
 @export var build_cost: int
+@export var build_resource_costs: Dictionary = {}
 @export var build_time: float = 10.0
 @export var icon: int = 2
 @export var glow_color: Color = Color(0.25, 0.85, 1.0)
@@ -21,6 +22,8 @@ extends Resource
 @export var unlock_name: String
 @export_multiline var unlock_description: String
 @export var unlock_cost: int
+@export var unlock_resource_costs: Dictionary = {}
+@export var unlock_icon: int = -1
 
 
 func has_capability(capability: String) -> bool: