fix: resolve ctx naming conflict in arr/config.js, add pylon to known config keys

- Remove redundant ctx shim that conflicted with function parameter
- Use destructured notification/safeErrorMessage directly
- Add pylon, customLogoDark, customLogoLight to known config keys

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

dashcaddy-api/config-schema.js

@@ -117,7 +117,8 @@ function validateConfig(config) {
     'setupComplete', 'setupCompleted', 'setupMode', 'onboardingCompleted',
     'configurationType', 'defaults', 'customLogo', 'customFavicon',
     'dashboardTitle', 'tailscale', 'license', 'skipped',
-    'routingMode', 'domain', 'email', 'defaultIP'
+    'routingMode', 'domain', 'email', 'defaultIP', 'pylon',
+    'customLogoDark', 'customLogoLight'
   ];
   for (const key of Object.keys(config)) {
     if (!knownKeys.includes(key)) {