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value receivers with pointer receivers in PacketID methods, expand FixedBitSet size from 8 to 256 bits, and remove outdated documentation files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_structure_block.go

@@ -21,7 +21,7 @@ type SetStructureBlock struct {
 	Flags                     int8
 }
 
-func (SetStructureBlock) PacketID() packetid.ServerboundPacketID {
+func (*SetStructureBlock) PacketID() packetid.ServerboundPacketID {
 	return packetid.ServerboundSetStructureBlock
 }