CVE-2026-45723: Omni: Operator can traverse image-factory API paths via unsanitized `talos_version` in CreateSchematic

managementServer.CreateSchematic (internal/backend/grpc/schematics.go) passes the caller-controlled TalosVersion field directly to imageFactoryClient.OverlaysVersions, which embeds it verbatim into a fmt.Sprintf("/version/%s/overlays/official", talosVersion) path template. url.URL.JoinPath resolves any ../ sequences in that path, allowing an authenticated Operator to rewrite the URL path and force Omni to issue HTTP GET requests to unintended paths on the configured image-factory server. Error body content from those unintended endpoints is returned to the caller.