fix(payment): resolve PR audit issues

- Add payment navigation to AppSidebar (user orders + admin payment menu group with collapse)
- Add 5 missing nav i18n keys (myOrders, orderManagement, paymentDashboard, paymentConfig, paymentPlans)
- Renumber payment migrations 090-100 → 092-102 to avoid conflict with upstream 090/091
- Remove non-payment sora_client_enabled change, restore upstream purchase_subscription fields
- Remove extra 'data' from SettingsTab type union

frontend/src/views/admin/SettingsView.vue

@@ -2498,7 +2498,7 @@ const { t } = useI18n()
 const appStore = useAppStore()
 const adminSettingsStore = useAdminSettingsStore()
 
-type SettingsTab = 'general' | 'security' | 'users' | 'gateway' | 'payment' | 'email' | 'backup' | 'data'
+type SettingsTab = 'general' | 'security' | 'users' | 'gateway' | 'payment' | 'email' | 'backup'
 const activeTab = ref<SettingsTab>('general')
 const settingsTabs = [
   { key: 'general'  as SettingsTab, icon: 'home'   as const },
@@ -2613,7 +2613,8 @@ const form = reactive<SettingsForm>({
   backend_mode_enabled: false,
   hide_ccs_import_button: false,
   payment_enabled: false,  payment_min_amount: 1,  payment_max_amount: 10000,  payment_daily_limit: 50000,  payment_max_pending_orders: 3,  payment_order_timeout_minutes: 30,  payment_balance_disabled: false,  payment_enabled_types: [],  payment_help_image_url: '',  payment_help_text: '',  payment_product_name_prefix: '',  payment_product_name_suffix: '',  payment_load_balance_strategy: 'round-robin',  payment_cancel_rate_limit_enabled: false,  payment_cancel_rate_limit_max: 10,  payment_cancel_rate_limit_window: 1,  payment_cancel_rate_limit_unit: 'day',  payment_cancel_rate_limit_window_mode: 'rolling',
-  sora_client_enabled: false,
+  purchase_subscription_enabled: false,
+  purchase_subscription_url: '',
   custom_menu_items: [] as Array<{id: string; label: string; icon_svg: string; url: string; visibility: 'user' | 'admin'; sort_order: number}>,
   custom_endpoints: [] as Array<{name: string; endpoint: string; description: string}>,
   frontend_url: '',