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/config/backup.js

@@ -5,6 +5,7 @@ const { CADDY } = require('../../constants');
 const { exists } = require('../../fs-helpers');
 const { ValidationError, AuthenticationError } = require('../../errors');
 const platformPaths = require('../../platform-paths');
+const { ok } = require('../../src/utils/responses');
 
 /**
  * Config backup routes factory
@@ -210,7 +211,7 @@ module.exports = function(deps) {
       preview.browserStateCount = Object.keys(backup.browserState).length;
     }
 
-    res.json({ success: true, preview });
+    ok(res, { preview });
   }, 'backup-preview'));
 
   // Restore configuration from backup
@@ -391,13 +392,17 @@ module.exports = function(deps) {
 
     const success = results.restored.length > 0 && results.errors.length === 0;
 
-    res.json({
-      success,
-      message: success
-        ? `Restored ${results.restored.length} file(s) successfully`
-        : `Restore completed with ${results.errors.length} error(s)`,
-      results
-    });
+    if (success) {
+      ok(res, {
+        message: `Restored ${results.restored.length} file(s) successfully`,
+        results
+      });
+    } else {
+      ok(res, {
+        message: `Restore completed with ${results.errors.length} error(s)`,
+        results
+      }, 200);
+    }
 
     log.info('backup', 'Backup restore completed', { restored: results.restored.length, errors: results.errors.length });
   }, 'backup-restore'));