feat: add /setmaxplayers command

server/src/main/java/org/allaymc/server/command/defaults/SetMaxPlayersCommand.java

@@ -0,0 +1,32 @@
+package org.allaymc.server.command.defaults;
+
+import org.allaymc.api.command.SimpleCommand;
+import org.allaymc.api.command.tree.CommandTree;
+import org.allaymc.api.i18n.TrKeys;
+import org.allaymc.api.server.Server;
+
+/**
+ * @author daoge_cmd
+ */
+public class SetMaxPlayersCommand extends SimpleCommand {
+
+    public SetMaxPlayersCommand() {
+        super("setmaxplayers", TrKeys.M_COMMANDS_SETMAXPLAYERS_DESCRIPTION);
+    }
+
+    @Override
+    public void prepareCommandTree(CommandTree tree) {
+        tree.getRoot()
+                .intNum("maxPlayers")
+                .exec(context -> {
+                    int maxPlayers = context.getResult(0);
+                    maxPlayers = Math.max(Server.getInstance().getOnlinePlayerCount(), maxPlayers);
+
+                    Server.SETTINGS.genericSettings().maxClientCount(maxPlayers);
+                    Server.getInstance().getNetworkServer().setMaxPlayerCount(maxPlayers);
+                    context.addOutput(TrKeys.M_COMMANDS_SETMAXPLAYERS_SUCCESS, maxPlayers);
+
+                    return context.success();
+                });
+    }
+}

server/src/main/java/org/allaymc/server/registry/AllayCommandRegistry.java

@@ -69,6 +69,7 @@ private void registerDefaultCommands() {
         register(new ClearCommand());
         register(new KillCommand());
         register(new SummonCommand());
+        register(new SetMaxPlayersCommand());
     }
 
     @Override