Update to Minecraft 1.21.8, add checkstyle, fix compilation errors

- Update Paper API: 1.20.1 -> 1.21.4
- Update plugin version: 1.5.5-1.20.1 -> 1.5.5-1.21.8
- Add checkstyle plugin with reasonable rules
- Fix Enchantment.LUCK -> Enchantment.UNBREAKING
- Fix EntityType.FIREWORK -> EntityType.FIREWORK_ROCKET
- Remove unused imports
- Add temp_*/ to .gitignore
- 118 files changed, 1633 insertions(+), 1301 deletions(-)

src/main/java/com/loki/lochat/commands/GlobalChatCommand.java

@@ -18,9 +18,9 @@ import org.jetbrains.annotations.NotNull;
  */
 public class GlobalChatCommand implements CommandExecutor {
 
+    private static final MiniMessage MM = MiniMessage.miniMessage();
     private final LoChat plugin;
     private final ChatService chatService;
-    private static final MiniMessage MM = MiniMessage.miniMessage();
 
     public GlobalChatCommand(LoChat plugin) {
         this.plugin = plugin;
@@ -53,10 +53,10 @@ public class GlobalChatCommand implements CommandExecutor {
         }
 
         String message = String.join(" ", args);
-        
+
         // Конвертируем String в Component для новой сигнатуры ChatService
         Component messageComponent = MM.deserialize(message);
-        
+
         chatService.sendGlobalMessage(player, messageComponent);
         return true;
     }