Add Uuid.Nil

src/util.zig

@@ -22,6 +22,8 @@ pub fn getRandom() std.rand.Random {
 pub const Uuid = struct {
     data: [16]u8,
 
+    pub const Nil = Uuid{ .data = @bitCast([16]u8, @as(u128, 0)) };
+
     pub fn eql(lhs: Uuid, rhs: Uuid) bool {
         return std.mem.eql(u8, &lhs.data, &rhs.data);
     }