feat(blocks): add ore block scaffolding (Coal, Iron, Gold, Diamond)

VoxelEngine.Tests/BlockRegistryTests.cs

@@ -71,4 +71,36 @@ public class BlockRegistryTests
         Assert.Equal("Snow Block", registry.Get(5).Name);
         Assert.Equal("Water", registry.Get(6).Name);
     }
+
+    [Fact]
+    public void Registry_ResolvesOreBlocks_ByStableIds()
+    {
+        var registry = new BlockRegistry();
+
+        Assert.Equal("Coal Ore",    registry.Get(7).Name);
+        Assert.Equal("Iron Ore",    registry.Get(8).Name);
+        Assert.Equal("Gold Ore",    registry.Get(9).Name);
+        Assert.Equal("Diamond Ore", registry.Get(10).Name);
+    }
+
+    [Fact]
+    public void Ores_AreOpaqueAndSolid()
+    {
+        var registry = new BlockRegistry();
+        foreach (ushort id in new ushort[] { 7, 8, 9, 10 })
+        {
+            Assert.True(registry.Get(id).IsOpaque, $"ore id {id} should be opaque");
+            Assert.True(registry.Get(id).IsSolid,  $"ore id {id} should be solid");
+        }
+    }
+
+    [Fact]
+    public void NamedOreAccessors_MatchIds()
+    {
+        var registry = new BlockRegistry();
+        Assert.Equal((ushort)7,  registry.CoalOre.Id);
+        Assert.Equal((ushort)8,  registry.IronOre.Id);
+        Assert.Equal((ushort)9,  registry.GoldOre.Id);
+        Assert.Equal((ushort)10, registry.DiamondOre.Id);
+    }
 }