Implement production vertical slice foundation

game/domain/dive/depth_snapshot.gd

@@ -0,0 +1,19 @@
+class_name DepthSnapshot
+extends RefCounted
+
+var current_m: float
+var certified_m: float
+var critical_m: float
+var crush_m: float
+
+
+func _init(
+	p_current_m: float,
+	p_certified_m: float,
+	p_critical_m: float,
+	p_crush_m: float
+) -> void:
+	current_m = p_current_m
+	certified_m = p_certified_m
+	critical_m = p_critical_m
+	crush_m = p_crush_m