Complete Stage 0: Project scaffold

- Fix build.gradle.kts: Java 21, Paper 1.20.6, ProtocolLib 5.3.0
- Add permissions to paper-plugin.yml
- Add ConfigManager with safe yaml loading (no overwrite)
- Add LocationsConfig for all game object coordinates
- Add GameConfig with all balance values
- Update mdbd.java with onEnable/onDisable + ConfigManager
- Mark Stage 0 complete in PLAN.md

src/main/resources/paper-plugin.yml

@@ -4,7 +4,15 @@ version: '${version}'
 main: dev.loki.mdbd
 bootstrapper: dev.loki.mdbdBootstrap
 loader: dev.loki.mdbdLoader
-api-version: '26.1.2'
+api-version: '1.20.6'
 load: POSTWORLD
 
 authors: [ loki ]
+
+permissions:
+  mdbd.admin:
+    description: "Полный доступ к админ-командам плагина"
+    default: op
+  mdbd.player:
+    description: "Базовые команды для игроков"
+    default: true