refactor(editor): reorganize Editor directory and unify menu hierarchy

File directory changes (mirror Scripts/ module structure):
- AbilityTypeDrawer.cs         → Equipment/
- CharacterWizardWindow.cs     → Character/
- FormEditorWindow.cs          → Player/
- GMToolWindow.cs              → Tools/
- SOManagerWindow.cs           → Tools/
- Map/MapRoomDataEditor.cs     → World/Map/
- Navigation/ (root)           → Enemies/Navigation/
- Achievements/                → Progression/

Menu hierarchy changes (BaseGames/ top-level):
- Data/: +Character Wizard (from Tools/), +Boss Skill Sequence (from Tools/)
- Addressables/: +Addressable Batch Tool, +Asset Reference Graph, +Validate Address Keys (from Tools/Verification/)
- Scene/Setup/: +Boot Flow Wizard, +Scaffold *, +Auto-Open Persistent (from Tools/)
- Scene/: +Camera Area Setup (from Camera/), +Bake All NavSurfaces (from Tools/)
- Events/: +Event Bus Monitor, +Event Chain Viewer, +Create/Reimport Event Channels (from Tools/)
- Tools/Validation/: +Validate All SOs, +Apply/Validate Script Order (from Tools/ flat)
- Tools/Maintenance/: +Missing Scripts/*, +Physics2D Layer Matrix/* (from Tools/ flat)

Result: BaseGames/Tools/ reduced from 16 flat items to 4 items + 2 submenus

Docs: update AssetFolderSpec §12 editor tool table with new menu paths

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Assets/_Game/Scripts/Editor/Tools/MissingScriptCleaner.cs

@@ -15,7 +15,7 @@ namespace BaseGames.Editor
         // 场景
         // ──────────────────────────────────────────────
 
-        [MenuItem("BaseGames/Tools/Missing Scripts/Clear In Scene")]
+        [MenuItem("BaseGames/Tools/Maintenance/Missing Scripts/Clear In Scene")]
         public static void ClearMissingScriptsInScene()
         {
             int totalRemoved = 0;
@@ -39,7 +39,7 @@ namespace BaseGames.Editor
                 Debug.Log($"[MissingScriptCleaner] 场景完成。共移除 {totalRemoved} 个丢失脚本，影响 {affected.Count} 个 GameObject。");
         }
 
-        [MenuItem("BaseGames/Tools/Missing Scripts/Find In Scene")]
+        [MenuItem("BaseGames/Tools/Maintenance/Missing Scripts/Find In Scene")]
         public static void FindMissingScriptsInScene()
         {
             int totalFound = 0;
@@ -67,7 +67,7 @@ namespace BaseGames.Editor
         // Prefab 资产
         // ──────────────────────────────────────────────
 
-        [MenuItem("BaseGames/Tools/Missing Scripts/Clear In All Prefabs")]
+        [MenuItem("BaseGames/Tools/Maintenance/Missing Scripts/Clear In All Prefabs")]
         public static void ClearMissingScriptsInPrefabs()
         {
             int totalRemoved = 0;
@@ -107,7 +107,7 @@ namespace BaseGames.Editor
                 Debug.Log($"[MissingScriptCleaner] Prefab 完成。共移除 {totalRemoved} 个丢失脚本，影响 {affectedPrefabs} 个 Prefab。");
         }
 
-        [MenuItem("BaseGames/Tools/Missing Scripts/Find In All Prefabs")]
+        [MenuItem("BaseGames/Tools/Maintenance/Missing Scripts/Find In All Prefabs")]
         public static void FindMissingScriptsInPrefabs()
         {
             int totalFound = 0;