CLI, along with several examples, plus model downloading

examples/scenes/ace.toml

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+# The Advanced Composition Explorer (26k triangles). The real ACE sits at the
+# Sun-Earth L1 point; here it is put in low orbit, in an isometric view with
+# Earth's limb behind it. Generated by scripts/make-example-scenes.py; the model
+# comes from scripts/fetch-models.sh.
+#
+#   resolved render --scene examples/scenes/ace.toml --preview ace.png
+
+sun = [111172883513, -100100513931, 0]
+moon = [0, 0, -3.844e8]
+
+[observer]
+position = [7000036.38, -73.51, 0.00]
+look_at = [7000000.00, 0.00, 0.00]
+up = [1, 0, 0]
+
+[[target]]
+model = "../models/nasa/ace.glb"
+scale = 0.00485
+position = [7000000.0000, 0.0000, 0.0000]
+attitude = [0.218913627, -0.630230282, 0.320639661, -0.672366584]