fix(core): Removes implicit cast between Serial and uint (#728)

* Fixes spellbooks using serial ctor
* Fixes misc items where someone thought they had an amount and it didn't
* Fixes all `Food` types.

Projects/Benchmarks/Benchmarks/Packets/BenchmarkPacketBroadcast.cs

@@ -27,7 +27,7 @@ namespace Benchmarks
             var writer = new CircularBufferWriter(buffer);
             writer.Write((byte)0xAE);
             writer.Write((ushort)(50 + text.Length * 2));
-            writer.Write(serial);
+            writer.Write(serial.Value);
             writer.Write((short)graphic);
             writer.Write((byte)type);
             writer.Write((short)hue);