Add commands subfolder with template CommandExecutor

[Copilot]

The template lacked any example of command handling, leaving developers without a starting point for adding slash commands to their plugins.

Changes

• commands/PapermcPluginTemplateCommand.java — New commands/ package containing a CommandExecutor template with thorough Javadoc explaining the full command registration workflow (handler implementation, plugin.yml declaration, and main class wiring), mirroring the doc style of PapermcPluginTemplateListener
• plugin.yml — Adds a commands: section registering the example /hello command
• PapermcPluginTemplatePlugin.java — Wires up the executor in setup() via Objects.requireNonNull(getCommand("hello")).setExecutor(...)

Example

// commands/PapermcPluginTemplateCommand.java
public class PapermcPluginTemplateCommand implements CommandExecutor {
    @Override
    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
        if (sender instanceof Player player) {
            player.sendMessage("Hello " + player.getName() + "! (from PapermcPluginTemplate)");
        } else {
            sender.sendMessage("This command can only be run by a player.");
        }
        return true;
    }
}

# plugin.yml
commands:
  hello:
    description: Greet the player.
    usage: /hello

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• hub.spigotmc.org
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.prefs/java.util.prefs=ALL-UNNAMED --add-opens=java.base/java.nio.charset=ALL-UNNAMED --add-opens=java.base/java.net=ALL-UNNAMED --add-opens=java.base/java.util.concurrent.atomic=ALL-UNNAMED -XX:MaxMetaspaceSize=384m -XX:+HeapDumpOnOutOfMemoryError -Xms256m -Xmx512m -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -cp /home/REDACTED/.gradle/wrapper/dists/gradle-8.0.2-bin/25jlreiuz6u3xu2phlpa2vv4m/gradle-8.0.2/lib/gradle-launcher-8.0.2.jar org.gradle.launcher.daemon.bootstrap.GradleDaemon 8.0.2 (dns block)
• repo.papermc.io
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.prefs/java.util.prefs=ALL-UNNAMED --add-opens=java.base/java.nio.charset=ALL-UNNAMED --add-opens=java.base/java.net=ALL-UNNAMED --add-opens=java.base/java.util.concurrent.atomic=ALL-UNNAMED -XX:MaxMetaspaceSize=384m -XX:+HeapDumpOnOutOfMemoryError -Xms256m -Xmx512m -Dfile.encoding=UTF-8 -Duser.country -Duser.language=en -Duser.variant -cp /home/REDACTED/.gradle/wrapper/dists/gradle-8.0.2-bin/25jlreiuz6u3xu2phlpa2vv4m/gradle-8.0.2/lib/gradle-launcher-8.0.2.jar org.gradle.launcher.daemon.bootstrap.GradleDaemon 8.0.2 (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)