chore: Enable DCM rule double-literal-format (#3248)

Enable DCM rule double-literal-format.

More details
[here](https://dcm.dev/docs/rules/common/double-literal-format/). This
both forbids trailing zeroes and mandates leading zeroes.

If we would prefer a different style (e.g. prefer no leading zero
instead), just lmk :)

examples/lib/stories/collision_detection/multiple_shapes_example.dart

@@ -263,7 +263,7 @@ class CollidableSnowman extends MyCollidable {
     );
     final middle = SnowmanPart(
       size.x * 0.4,
-      Vector2(size.x / 2, size.y * 0.40),
+      Vector2(size.x / 2, size.y * 0.4),
       Colors.yellow,
     );
     final bottom = SnowmanPart(