MC-4: Fix item position desync

This fixes item position desync (MC-4) by running the item coordinates
through the encode/decode methods of the packet that causes the precision
loss, which forces the server to lose the same precision as the client
keeping them in sync.

paper-server/patches/sources/net/minecraft/network/protocol/game/VecDeltaCodec.java.patch

@@ -0,0 +1,17 @@
+--- a/net/minecraft/network/protocol/game/VecDeltaCodec.java
++++ b/net/minecraft/network/protocol/game/VecDeltaCodec.java
+@@ -9,12 +9,12 @@
+ 
+     @VisibleForTesting
+     static long encode(double value) {
+-        return Math.round(value * 4096.0);
++        return Math.round(value * 4096.0); // Paper - Fix MC-4; diff on change
+     }
+ 
+     @VisibleForTesting
+     static double decode(long value) {
+-        return (double)value / 4096.0;
++        return value / 4096.0; // Paper - Fix MC-4; diff on change
+     }
+ 
+     public Vec3 decode(long x, long y, long z) {