Fix performAdvancedSearch ReferenceError, settings save, sort reset, notifications 500, CSP

DashboardView.php: wrap performAdvancedSearch in a closure so it is
resolved at event-fire time rather than listener-registration time
(advanced-search.js loads later via pageScripts so the bare identifier
reference caused ReferenceError).

DashboardView.php: reset sort URL to page=1 so sorting all pages
instead of staying on the current page.

dashboard.js: add missing save-settings and close-settings cases to
the click delegation handler (were removed in a prior session under
the assumption they were in dashboard.js, but they were not).

notifications.php: replace JSON_EXTRACT-based comment join (not
universally supported) with a two-step PHP filter: fetch owner/watcher
ticket IDs first, then filter raw comment rows in PHP. Also fix the
status change LIKE pattern to match the actual logTicketUpdate format
{"status": {"from": ..., "to": ...}}.

SecurityHeadersMiddleware.php: add https://cdn.jsdelivr.net to
connect-src so Chart.js source maps load without CSP violations.

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

middleware/SecurityHeadersMiddleware.php

@@ -28,7 +28,7 @@ class SecurityHeadersMiddleware {
         // Content Security Policy - restricts where resources can be loaded from
         // Using nonces for scripts to prevent XSS attacks while allowing inline scripts with valid nonces
         // All inline event handlers have been refactored to use addEventListener with data-action attributes
-        header("Content-Security-Policy: default-src 'self'; script-src 'self' 'nonce-{$nonce}' https://cdn.jsdelivr.net; style-src 'self' 'unsafe-inline' https://fonts.googleapis.com https://cdn.jsdelivr.net; img-src 'self' data:; font-src 'self' https://fonts.gstatic.com; connect-src 'self';");
+        header("Content-Security-Policy: default-src 'self'; script-src 'self' 'nonce-{$nonce}' https://cdn.jsdelivr.net; style-src 'self' 'unsafe-inline' https://fonts.googleapis.com https://cdn.jsdelivr.net; img-src 'self' data:; font-src 'self' https://fonts.gstatic.com; connect-src 'self' https://cdn.jsdelivr.net;");
 
         // Prevent clickjacking by disallowing framing
         header("X-Frame-Options: DENY");