feat: reject eligible/reviewed wording for already-landed PRs (Closes #298)

Add assess_already_landed_report_wording to review_proofs: when the
already-landed gate fires, final reports and controller handoffs must
use the reconciliation wording (Oldest open PR requiring action,
Eligibility class: ALREADY_LANDED_RECONCILE_REQUIRED, Candidate head
SHA, Reviewed head SHA: none, Review worktree used: false) and must not
use the legacy fields (oldest/next eligible PR, Pinned reviewed head,
Scratch worktree used) or claim a reviewed head SHA. In
non-already-landed reports, a populated Pinned reviewed head or
Reviewed head SHA fails unless validation and diff review actually
passed this session. Fails closed. Tests cover the correct
reconciliation wording, each forbidden legacy field, missing required
fields, populated reviewed SHA, normal reviewed reports, blocked-infra
reports, and validation-failed reports.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

review_proofs.py

@@ -1171,6 +1171,102 @@ def assess_workspace_mutation_consistency(report_text, observed_commands=None):
     }
 
 
+# ── Already-landed report wording (Issue #298) ───────────────────────────────
+#
+# An already-landed PR is reconciliation-only: it must never be called
+# eligible, its head SHA must never be called reviewed, and the legacy
+# eligible/reviewed/scratch-worktree handoff fields must not appear.
+# Reviewed-head claims in any report require validation + diff review to
+# have actually passed.
+
+ALREADY_LANDED_FORBIDDEN_PHRASES = (
+    "oldest eligible pr",
+    "next eligible pr",
+    "pinned reviewed head",
+    "scratch worktree used",
+)
+
+ALREADY_LANDED_ELIGIBILITY_CLASS = "ALREADY_LANDED_RECONCILE_REQUIRED"
+
+
+def assess_already_landed_report_wording(report_text, *, already_landed,
+                                         review_validated=False):
+    """#298: reject eligible/reviewed wording for already-landed PRs.
+
+    *already_landed* states whether the already-landed gate fired for the
+    selected PR. *review_validated* states whether validation and diff
+    review actually passed this session; only then may a reviewed head
+    SHA be populated in a non-already-landed report.
+
+    Returns {'complete', 'downgraded', 'reasons'}; fails closed.
+    """
+    text_lower = (report_text or "").lower()
+    fields = _report_labeled_fields(report_text)
+    reasons = []
+
+    reviewed_head = fields.get("reviewed head sha")
+    reviewed_head_populated = bool(
+        reviewed_head and not reviewed_head.strip().lower().startswith("none")
+    )
+    pinned_head_present = "pinned reviewed head" in fields
+
+    if already_landed:
+        for phrase in ALREADY_LANDED_FORBIDDEN_PHRASES:
+            if phrase in text_lower:
+                reasons.append(
+                    f"already-landed report must not use '{phrase}'; the PR "
+                    "is reconciliation-only, not review/merge eligible"
+                )
+
+        eligibility = fields.get("eligibility class", "")
+        if ALREADY_LANDED_ELIGIBILITY_CLASS not in eligibility.upper():
+            reasons.append(
+                "already-landed report missing 'Eligibility class: "
+                f"{ALREADY_LANDED_ELIGIBILITY_CLASS}'"
+            )
+
+        for required in ("oldest open pr requiring action",
+                         "candidate head sha"):
+            if required not in fields:
+                reasons.append(
+                    f"already-landed report missing '{required}' field"
+                )
+
+        if "reviewed head sha" not in fields:
+            reasons.append(
+                "already-landed report must state 'Reviewed head SHA: none'"
+            )
+        elif reviewed_head_populated:
+            reasons.append(
+                "already-landed report must not claim a reviewed head SHA; "
+                "no validation or diff review passed for this PR"
+            )
+
+        worktree_used = fields.get("review worktree used", "")
+        if worktree_used.strip().lower() not in ("false", "no"):
+            reasons.append(
+                "already-landed report must state 'Review worktree used: "
+                "false'"
+            )
+    elif not review_validated:
+        if pinned_head_present:
+            reasons.append(
+                "'Pinned reviewed head' populated before validation and "
+                "diff review passed"
+            )
+        if reviewed_head_populated:
+            reasons.append(
+                "reviewed head SHA populated before validation and diff "
+                "review passed"
+            )
+
+    return {
+        "complete": not reasons,
+        "downgraded": bool(reasons),
+        "reasons": reasons,
+    }
+
+
 def assess_role_boundary(proof=None, *, task_role=None, namespaces_used=None,
                          justification=None):
     """Assess reviewer/author role separation for blind queue workflows.