Route async-delegation completions by the immutable origin_ui_session_id (exact origin tab) and deliver them through a durable claim/complete/release lifecycle so they arrive exactly once, restart-safe, on both the background wakeup and next-turn drain paths. Combines #6185 (@carlotestor) + #6159 (@sysophelper-droid); supersedes #6002/#6225.
Co-authored-by: carlotestor <carlotestor@users.noreply.github.com>
Co-authored-by: sysophelper-droid <sysophelper-droid@users.noreply.github.com>
_drain_webui_process_notifications now drops (consumes, never requeues) a
completion whose completed_at is older than a configurable cap
(HERMES_WEBUI_STALE_COMPLETION_MAX_AGE_SECONDS, default 6h; 0 disables).
Fail-open: events without completed_at (legacy agent) are never dropped.
Additive (+192/-0). Closes#4029.
Co-authored-by: allenliang2022
Co-authored-by: nesquena-hermes <agent@nesquena-hermes>
