Make iron darker, tweak copper, tweak gold block (#1411)

assets/cubyz/items/copper_ingot.zig.zon

@@ -7,7 +7,7 @@
 		.hardness = 3.0,
 		.textureRoughness = 0.1,
 		.colors = .{
-			0xffa25138, 0xffb66440, 0xffd5834b, 0xffec9568, 0xfff5b47e,
+			0xffa24e37, 0xffb65f3f, 0xffd57e4b, 0xffee9168, 0xfff2b17e,
 		},
 	},
 }

assets/cubyz/items/iron_ingot.zig.zon

@@ -7,7 +7,7 @@
 		.hardness = 5.0,
 		.textureRoughness = 0.1,
 		.colors = .{
-			0xff69696b, 0xff878484, 0xffa3a3a3, 0xffc2c2c2, 0xffe9e9e9,
+			0xff616163, 0xff797777, 0xff9c9c9c, 0xffb4b4b4, 0xffd9d9d9,
 		},
 	},
 }