Land deferred PE-2 lineage observability (panel_voter_lineage_unknown) — held in local stash

[omerakben]

Deferred PE-2 (OpenRouter) lineage-observability feature, currently held in a local git stash (stash@{0}) — not on any branch or remote.

What it is: +164 lines across 3 files adding a new panel_voter_lineage_unknown event type plus an emitter loop in runReviewPanel, with a full test:

• src/phases/review-panel.ts (+29)
• src/state/schemas.ts (+52)
• tests/review-panel-orchestrator.test.ts (+83)

Status: Confirmed absent from main (verified by the 2026-05-29 branch-cleanup audit — git grep panel_voter_lineage_unknown origin/main -- src/ returns nothing). Main's handoff docs (CODEX_BRIEFING_OPENCODE_R_MERGE.md, handoffs/2026-05-12-session-3-opencode-triage.md) explicitly set its disposition to "keep stashed" pending a future R-merge value call.

To land it later:

• Rebase onto the current src/state/schemas.ts OptionalActorAttributed<> wrapping (the stash predates it).
• Add a strict validator case in src/state/events.ts.
• Original stash base was worktree-opencode-fixfirst @ 4870a32 (branch since deleted; that commit is an ancestor of main).

Caveat: this code lives only in a local stash on the maintainer's machine. git stash clear would destroy it. Consider git stash branch <name> stash@{0} to a durable branch if it will not be landed soon.

[omerakben]

Backed up to durable branch feat/issue-42-pe2-lineage-observability (commit b975f1c), pushed to origin during the 2026-05-29 cleanup. The local stash was consumed in the conversion (no longer in git stash list) — this branch is now the single source of truth. Content unchanged: 3 files / +164 (src/phases/review-panel.ts, src/state/schemas.ts, tests/review-panel-orchestrator.test.ts) on base 4870a32. Landing still needs the rebase noted in the issue body.