PYSEC-2026-3603 Open WebUI: `WEB_FETCH_FILTER_LIST` host allow/block filter bypassable via URL path and non-label-boundary matching

Summary The administrator-configured WEBFETCHFILTERLIST the allow/block list applied to server-side web fetches: RAG URL ingestion, URL-to-markdown, web-search content fetch matches hostnames incorrectly, so the filter can be bypassed. Details isstringallowed backend/openwebui/utils/misc.py match...