docs(bukkit): 添加部分文档

hamster-core-bukkit/src/main/java/cn/hamster3/mc/plugin/core/bukkit/command/ParentCommand.java

@@ -23,6 +23,9 @@ public abstract class ParentCommand extends ChildCommand {
         childCommands = new ArrayList<>();
     }
 
+    @NotNull
+    public abstract JavaPlugin getPlugin();
+
     @Override
     public @NotNull String getName() {
         return name;
@@ -33,15 +36,13 @@ public abstract class ParentCommand extends ChildCommand {
         return null;
     }
 
-    @NotNull
-    public abstract JavaPlugin getPlugin();
-
     @NotNull
     public List<ChildCommand> getChildCommands() {
         return childCommands;
     }
 
     @NotNull
+    @Override
     public String getUsage() {
         if (getParent() == null) {
             return "/" + name;
@@ -59,6 +60,13 @@ public abstract class ParentCommand extends ChildCommand {
         return "";
     }
 
+    /**
+     * 获取所有子命令
+     * <p>
+     * 如果子命令也是 ParentCommand 类型，则继续递归获取该 ParentCommand 的子命令
+     *
+     * @return 所有子命令
+     */
     @NotNull
     public List<ChildCommand> getEndChildCommands() {
         ArrayList<ChildCommand> list = new ArrayList<>();