Add the changelog fragment

changelog.d/1730-airport-vehicle-models.md

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+- Draw airport ground vehicles as real shapes instead of stacked boxes: the
+  car is an operations SUV, the van a high-roof panel van, the fire truck an
+  airport crash tender with turrets and the pushback a low tug with a glazed
+  cab, all on the ground at their built size (samehkhamis, #1730).