s-ui-x-extended v1.0.0-beta8

Pre-release. This release follows v1.0.0-beta7 and focuses on panel support for sing-box-extended control-plane features and option coverage.

Changes since beta7

• Added panel-owned outbound groups and provider-backed group membership for selector, URLTest, fallback, and failover flows.
• Added failover state, outbound health, provider health, bounded realtime payloads, and a Nexus overview widget for operational health.
• Added explicit all-down failover policies. The default keeps the current member. Direct fallback is available only when selected.
• Added panel support for outbound block, native core failover outbound, inbound bond, and native core failover inbound.
• Added shared inbound advanced fields, outbound domain_strategy, endpoint advanced fields, and protocol-specific option coverage in TypeScript and UI where safe to edit.
• Added provider entries to /api/capabilities and frontend generated capability types.
• Added a generated option coverage matrix and a drift test against the sing-box-extended option structs. The current matrix has zero unexplained missing fields.
• Kept the core dependency unchanged. All work is in the panel layer.

Upgrade notes

No manual database migration is needed. The binary runs the normal migration chain on startup. If upgrading from a previous s-ui-x-extended beta, the settings.version row is updated to 1.0.0-beta8 automatically.

Panel-managed failover does not provide generic session recovery. It switches new connections; existing sessions may break when the active member changes.

See CHANGELOG-EN.md, CHANGELOG-RU.md, and CHANGELOG-ZH.md for the full history. This is a pre-release. Review SECURITY.md before exposing the panel.