feat(admin): 更新后台权限管理与同步逻辑，简化权限检查并优化文档

- 新增后台 RBAC 相关文档，提供权限目录与维护命令说明。
- 移除不必要的角色资源同步检查，简化权限审计命令。
- 更新权限描述与同步逻辑，确保一致性与可维护性。
- 统一权限注册表，替换过时的权限别名，增强代码可读性。

app/Http/Controllers/Api/V1/Admin/AdminSettingController.php

@@ -37,15 +37,12 @@ final class AdminSettingController extends Controller
     public function update(AdminSettingUpdateRequest $request, string $key): JsonResponse
     {
         $setting = LotterySetting::query()->where('setting_key', $key)->first();
-        if ($setting === null) {
-            return ApiResponse::error('Setting not found', 404);
-        }
 
         LotterySettings::put(
             $key,
             $request->validated('value'),
-            $setting->group_name,
-            $setting->description_zh,
+            $setting ? $setting->group_name : (explode('.', $key)[0] ?? 'general'),
+            $setting ? $setting->description_zh : null,
         );
 
         $fresh = LotterySetting::query()->where('setting_key', $key)->first();

app/Http/Controllers/Api/V1/Admin/User/AdminUserPermissionSyncController.php

@@ -17,10 +17,10 @@ final class AdminUserPermissionSyncController extends Controller
     public function __invoke(AdminUserPermissionSyncRequest $request, AdminUser $admin_user): JsonResponse
     {
         $input = $request->validated();
-        $slugs = array_values(array_unique(array_values(array_filter(
+        $slugs = AdminPermissionBridge::normalizeCanonicalLegacySlugs(array_values(array_filter(
             (array) ($input['permissions'] ?? $input['permission_slugs'] ?? []),
             static fn ($v) => is_string($v) && $v !== '',
-        ))));
+        )));
         $siteId = AdminUser::defaultAdminSiteId();
 
         $codes = [];

app/Http/Controllers/Api/V1/Setting/SettingIndexController.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace App\Http\Controllers\Api\V1\Setting;
+
+use App\Http\Controllers\Controller;
+use App\Models\LotterySetting;
+use App\Support\ApiResponse;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Http\Request;
+
+/**
+ * 玩家端/公开：读取 KV 配置（公开访问）
+ */
+final class SettingIndexController extends Controller
+{
+    public function __invoke(Request $request): JsonResponse
+    {
+        $group = $request->query('group');
+        
+        $query = LotterySetting::query()->orderBy('setting_key');
+
+        if (! empty($group)) {
+            $query->where('group_name', $group);
+        }
+
+        $items = $query->get()->map(fn (LotterySetting $s): array => [
+            'key' => $s->setting_key,
+            'value' => $s->value_json,
+            'group' => $s->group_name,
+            'description' => $s->description_zh,
+        ]);
+
+        return ApiResponse::success(['items' => $items]);
+    }
+}