CVE-2026-39390: CI4MS has stored XSS via srcdoc attribute bypass in Google Maps iframe setting

The Google Maps iframe setting (cMap field) in compInfosPost() sanitizes input using strip_tags() with an <iframe> allowlist and regex-based removal of on\w+ event handlers. However, the srcdoc attribute is not an event handler and passes all filters. An attacker with admin settings access can inject an <iframe srcdoc="..."> payload with HTML-entity-encoded JavaScript that executes in the context of the parent page when rendered to unauthenticated frontend visitors.