feat(rbac): implement full admin management, dynamic roles, permissions matrix, and workspace access control

- Add Workspace, Role, Permission, RolePermission, AdminRoleAssignment, and AdminWorkspaceAssignment models to Prisma schema\n- Create database migration and RBAC seed script\n- Implement PermissionsGuard, @RequirePermission decorator, and real-time permission resolution in JwtAdminStrategy\n- Implement AdminManagementModule with endpoints for managers CRUD, roles matrix, permissions catalog, and workspaces\n- Secure all sensitive admin controllers with granular permission requirements\n- Add useAuthStore helpers (can, canAny, fetchMe) and v-permission directive\n- Implement Desktop views: AdminListView, AdminFormDrawer (RTL right-side), RoleMatrixView, WorkspaceListView, and ForbiddenView\n- Implement Mobile views: MAdminListView, MAdminFormView (stepped mobile form), MRoleMatrixView, MWorkspaceListView, and MForbiddenView\n- Fix sticky header behavior across desktop and mobile shells\n- Update route guards and device detection logic for mobile prefixing

apps/admin/src/views/errors/ForbiddenView.vue

@@ -0,0 +1,43 @@
+<script setup lang="ts">
+import { useRouter } from 'vue-router';
+
+const router = useRouter();
+
+function goHome() {
+  router.push('/dashboard');
+}
+</script>
+
+<template>
+  <div class="forbidden-page">
+    <a-card :bordered="false" class="forbidden-card">
+      <a-result
+        status="403"
+        title="۴۰۳ — دسترسی غیرمجاز"
+        sub-title="شما مجوز لازم برای مشاهده این بخش یا انجام این عملیات را در سامانه ندارید."
+      >
+        <template #extra>
+          <a-button type="primary" @click="goHome">
+            بازگشت به داشبورد
+          </a-button>
+        </template>
+      </a-result>
+    </a-card>
+  </div>
+</template>
+
+<style scoped>
+.forbidden-page {
+  padding: 40px 24px;
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  min-height: 70vh;
+}
+.forbidden-card {
+  max-width: 600px;
+  width: 100%;
+  border-radius: 12px;
+  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.04);
+}
+</style>