feat(gui): add mine editor GUI system

New GUI classes:
- MineEditGui.java - main editor with navigation to sub-editors
- MineEditGuiHolder.java - inventory holder for editor
- ConfirmDeleteGui.java - confirmation dialog for mine deletion
- ConfirmDeleteGuiHolder.java - inventory holder for confirmation
- MineEditGuiListener.java - handles clicks in editor GUIs

Updated:
- AdminCommands.java - add /lm edit <mine> command
- RegistrationManager.java - register MineEditGuiListener
- plugin.yml - add lomines.admin.edit permission

Features:
- Visual editor showing mine configuration sections
- Blocks, Regions, Reset, Rewards, Teleport, UI sections
- Save and Delete actions with confirmation
- Info panel showing mine status (blocks, volume, percent)

Sub-editors (placeholder, to be implemented):
- BlockEditGui - edit block types and weights
- ResetEditGui - edit reset interval and triggers
- RewardEditGui - edit mining rewards
- TeleportEditGui - edit teleport on reset
- UIEditGui - edit action bar settings

src/main/resources/plugin.yml

@@ -27,6 +27,7 @@ permissions:
       lomines.stats.others: true
       lomines.admin.wand: true
       lomines.admin.maskscan: true
+      lomines.admin.edit: true
   lomines.stats:
     description: View mining stats and leaderboards (/lm stats, /lm top)
     default: true
@@ -39,6 +40,9 @@ permissions:
   lomines.admin.wand:
     description: Group wand and /lm group prefix for batch mine creation
     default: op
+  lomines.admin.edit:
+    description: Open GUI editor for mines (/lm edit <mine>)
+    default: op
   lomines.use:
     description: Basic LoMines usage
     default: true