BGP-LS-SPF Extensions for SRv6 Policy State Synchronization

This document defines extensions to BGP-LS-SPF (BGP Link State Shortest Path First) to support synchronization of Segment Routing over IPv6 (SRv6) policy state information. It introduces a new optional Sub-TLV for the SRv6 End.X SID TLV that indicates whether an SRv6 SID is currently active in an SR policy. This enables dynamic interaction between SR policies and BGP-LS-SPF route computation, improving network responsiveness to policy changes.