Add support for protocol version 800 (1.21.80)

Introduced support for protocol 800, including biome definitions, camera presets, and player list updates. Upgraded dependencies, adjusted mappings, and enhanced the README to reflect recent changes.

legacyver/protocol.go

@@ -120,6 +120,10 @@ func convertPacketFunc(pid uint32, cur func() packet.Packet) func() packet.Packe
 		return func() packet.Packet { return &legacypacket.UpdatePlayerGameType{} }
 	case packet.IDSetActorMotion:
 		return func() packet.Packet { return &legacypacket.SetActorMotion{} }
+	case packet.IDBiomeDefinitionList:
+		return func() packet.Packet { return &legacypacket.BiomeDefinitionList{} }
+	case packet.IDPlayerList:
+		return func() packet.Packet { return &legacypacket.PlayerList{} }
 	default:
 		return cur
 	}
@@ -708,6 +712,20 @@ func (p *Protocol) downgradePackets(pks []packet.Packet, conn *minecraft.Conn) [
 				Elements:   pk.Elements,
 				Visibility: pk.Visibility,
 			}
+		case *packet.BiomeDefinitionList:
+			pks[pkIndex] = &legacypacket.BiomeDefinitionList{
+				BiomeDefinitions: pk.BiomeDefinitions,
+				StringList:       pk.StringList,
+			}
+		case *packet.PlayerList:
+			entries := make([]proto.PlayerListEntry, len(pk.Entries))
+			for i, e := range pk.Entries {
+				entries[i] = (&proto.PlayerListEntry{}).FromLatest(e)
+			}
+			pks[pkIndex] = &legacypacket.PlayerList{
+				ActionType: pk.ActionType,
+				Entries:    entries,
+			}
 		}
 	}
 
@@ -1213,6 +1231,20 @@ func (p *Protocol) upgradePackets(pks []packet.Packet, conn *minecraft.Conn) []p
 				Elements:   pk.Elements,
 				Visibility: pk.Visibility,
 			}
+		case *legacypacket.BiomeDefinitionList:
+			pks[pkIndex] = &packet.BiomeDefinitionList{
+				BiomeDefinitions: pk.BiomeDefinitions,
+				StringList:       pk.StringList,
+			}
+		case *legacypacket.PlayerList:
+			entries := make([]protocol.PlayerListEntry, len(pk.Entries))
+			for i, e := range pk.Entries {
+				entries[i] = e.ToLatest()
+			}
+			pks[pkIndex] = &packet.PlayerList{
+				ActionType: pk.ActionType,
+				Entries:    entries,
+			}
 		}
 	}
 	return pks