update protocol packet definitions: replace value receivers with pointer receivers in PacketID methods, expand FixedBitSet size from 8 to 256 bits, and remove outdated documentation files

pkg/protocol/packet/game/server/set_command_block.go

@@ -13,7 +13,7 @@ type SetCommandBlock struct {
 	Flags    int8
 }
 
-func (SetCommandBlock) PacketID() packetid.ServerboundPacketID {
+func (*SetCommandBlock) PacketID() packetid.ServerboundPacketID {
 	return packetid.ServerboundSetCommandBlock
 }