v1.13.4: Standardize all route responses to use response helpers

Convert ~160 raw res.json()/res.status().json() calls across 32+ files
to use centralized helpers from src/utils/responses.js (ok, errorResponse,
successMessage, notFound, validationError, forbidden, unauthorized, conflict).

No behavior changes — response shapes are identical. Future schema changes
(e.g., requestId envelope) only need to update one module.

Fix error vs errorResponse signature mismatch in routes/health.js CA cert
endpoint where error(res, message, statusCode) was being called with
errorResponse(res, statusCode, message, extras) argument order.

Files changed: middleware.js, csrf-protection.js, error-handler.js,
license-manager.js, src/app.js, and 27 route files.

Test suite: 755 pass / 4 pre-existing failures (services credential tests).

dashcaddy-api/routes/notifications.js

@@ -3,6 +3,7 @@ const { validateURL, validateToken } = require('../input-validator');
 const validatorLib = require('validator');
 const { paginate, parsePaginationParams } = require('../pagination');
 const { ValidationError } = require('../errors');
+const { ok, successMessage } = require('../src/utils/responses');
 
 /**
  * Notifications route factory
@@ -44,7 +45,7 @@ module.exports = function({ notification, asyncHandler }) {
         events: notificationConfig.events,
         healthCheck: notificationConfig.healthCheck
       };
-      res.json({ success: true, config: safeConfig });
+      ok(res, { config: safeConfig });
   }, 'notifications-config-get'));
 
   // POST /config — Update notification configuration
@@ -150,7 +151,7 @@ module.exports = function({ notification, asyncHandler }) {
       }
 
       await notification.saveConfig();
-      res.json({ success: true, message: 'Notification config updated' });
+      successMessage(res, 'Notification config updated');
   }, 'notifications-config-update'));
 
   // POST /test — Test notification delivery
@@ -176,11 +177,11 @@ module.exports = function({ notification, asyncHandler }) {
         default:
           throw new ValidationError('Unknown provider');
       }
-      res.json({ success: result.success, provider, error: result.error });
+      ok(res, { success: result.success, provider, error: result.error });
     } else {
       // Test all enabled providers
       const result = await notification.send('test', 'Test Notification', 'This is a test notification from DashCaddy.', 'info');
-      res.json({ success: true, ...result });
+      ok(res, { success: true, ...result });
     }
   }, 'notifications-test'));
 
@@ -190,11 +191,10 @@ module.exports = function({ notification, asyncHandler }) {
     const paginationParams = parsePaginationParams(req.query);
     if (paginationParams) {
       const result = paginate(notificationHistory, paginationParams);
-      res.json({ success: true, history: result.data, total: notificationHistory.length, pagination: result.pagination });
+      ok(res, { history: result.data, total: notificationHistory.length, pagination: result.pagination });
     } else {
       const limit = parseInt(req.query.limit) || 50;
-      res.json({
-        success: true,
+      ok(res, {
         history: notificationHistory.slice(0, limit),
         total: notificationHistory.length
       });
@@ -204,15 +204,14 @@ module.exports = function({ notification, asyncHandler }) {
   // DELETE /history — Clear notification history
   router.delete('/history', asyncHandler(async (req, res) => {
     notification.clearHistory();
-    res.json({ success: true, message: 'Notification history cleared' });
+    successMessage(res, 'Notification history cleared');
   }, 'notifications-history-clear'));
 
   // POST /health-check — Manually trigger health check
   router.post('/health-check', asyncHandler(async (req, res) => {
     await notification.checkHealth();
     const notificationConfig = notification.getConfig();
-    res.json({
-      success: true,
+    ok(res, {
       lastCheck: notificationConfig.healthCheck.lastCheck,
       containersMonitored: Object.keys(notification.getHealthState()).length
     });
@@ -223,8 +222,7 @@ module.exports = function({ notification, asyncHandler }) {
     const notificationConfig = notification.getConfig();
     const providers = notificationConfig.providers || {};
     
-    res.json({
-      success: true,
+    ok(res, {
       enabled: notificationConfig.enabled,
       providers: {
         discord: providers.discord?.enabled && !!providers.discord?.webhookUrl,
@@ -252,7 +250,7 @@ module.exports = function({ notification, asyncHandler }) {
     // Use 'test' as the event for manual sends
     const result = await notification.send(event, data || {}, type || 'info');
     
-    res.json({ 
+    ok(res, { 
       success: result.success, 
       event,
       results: result.results