feat(lohub): Add complete configuration system with 6 config files

- Added messages.yml for all plugin messages with customizable prefix
- Added commands.yml for custom commands (discord, website, store, rules, heal, clearinventory)
- Added serverselector.yml for GUI server selector menu
- Added data.yml for persistent data storage (chat_locked, spawn location)
- Updated ConfigManager to load all config files
- Updated ChatLockManager to use data.yml instead of chatlock.dat
- Updated SpawnManager to use data.yml instead of spawn.yml
- Updated all commands to use messages.yml
- Updated listeners to use messages.yml
- Removed duplicate config files from root directory
- Added CONFIG_GUIDE.md documentation

lohub/src/main/resources/data.yml

@@ -0,0 +1,17 @@
+# ╔══════════════════════════════════════════════════════════════════════════════╗
+# ║                           LoHub Data Storage                                ║
+# ║                  DO NOT EDIT THIS FILE MANUALLY!                           ║
+# ║              This file is automatically managed by the plugin              ║
+# ╚══════════════════════════════════════════════════════════════════════════════╝
+
+# Chat lock state
+chat_locked: false
+
+# Spawn location (set via /sethub command)
+spawn:
+  world: null
+  x: 0.0
+  y: 0.0
+  z: 0.0
+  yaw: 0.0
+  pitch: 0.0