Keep terminal live status accurate

[yvette-carlisle]

Summary

• Keep terminal attempts visible as running only when liveness evidence is real: live process, active thread, or active work-protocol execution.
• Preserve succeeded as raw attempt_status while surfacing a still-live child as operator status=running.
• Stop terminal maintenance events like thread/archive and completed-turn bookkeeping from making old failed/interrupted lanes appear active.

Root cause

Operator status previously treated recent protocol activity too broadly for terminal-looking attempts. A post-run maintenance event such as thread/archive could refresh last_protocol_activity_at and make landed/manual-handled lanes show up as running. Separately, a succeeded attempt with a still-live marker was hidden because terminal promotion skipped succeeded attempts.

Verification

• npm ci in site/
• cargo test -p decodex operator_status_snapshot_excludes_terminal_thread_archive_from_running_lanes -- --nocapture
• cargo test -p decodex operator_status_snapshot_keeps_succeeded_status_live_process_in_running_lanes -- --nocapture
• cargo test -p decodex operator_lane_interrupt_api_force_hard_fallbacks_after_succeeded_status_with_live_process -- --nocapture
• cargo make check
• git diff --check
• target/debug/decodex status --config /Users/x/.codex/decodex/projects/decodex --live --json returned active_count 0 for the current local ghost-lane repro.
• Semantic drift audit: pass by manual review against code/tests; helper stale phrase hits were generic uses of unavailable, not stale operator-status contract text.