Move and split up weather.py.

This is getting out of hand, and I'm about to make it worse.

game/weather/wind.py

@@ -0,0 +1,12 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+from dcs.weather import Wind
+
+
+@dataclass(frozen=True)
+class WindConditions:
+    at_0m: Wind
+    at_2000m: Wind
+    at_8000m: Wind