fix(stats): skip corrupt decided/*.yaml so vouch stats cannot crash

CHANGELOG.md

@@ -45,6 +45,10 @@ All notable changes to vouch are documented here. Format follows
   artifact the caller could not already retrieve, and it touches no write path.
 
 ### Fixed
+- **`vouch stats` / `kb.stats` no longer crash on one corrupt `decided/*.yaml`**:
+  `_list_decided` parsed every decided proposal strictly, so a single bad file
+  aborted `review_summary` / `collect_stats`. It now uses `_load_or_skip` —
+  same resilience as `list_proposals` / `list_pages`.
 - **rerank / recency / triage quoted `"true"` stays off** (#658):
   `retrieval.rerank.enabled`, `retrieval.recency.enabled` and
   `triage.enabled` were the last three readers still on the

src/vouch/stats.py

@@ -15,7 +15,7 @@
 from . import audit, health
 from .models import Proposal, ProposalStatus
 from .proposals import EXPIRE_REASON
-from .storage import KBStore, _yaml_load
+from .storage import KBStore, _load_or_skip
 
 if TYPE_CHECKING:
     from .scoping import ViewerContext
@@ -50,12 +50,19 @@ def _decision_bucket(proposal: Proposal) -> str:
 
 
 def _list_decided(store: KBStore) -> list[Proposal]:
+    """Load decided proposals for review_summary.
+
+    Uses ``_load_or_skip`` so one corrupt ``decided/*.yaml`` cannot take down
+    ``vouch stats`` / ``kb.stats`` — same resilience as ``list_proposals``.
+    """
     ddir = store.kb_dir / "decided"
     if not ddir.is_dir():
         return []
     out: list[Proposal] = []
     for path in sorted(ddir.glob("*.yaml")):
-        out.append(Proposal.model_validate(_yaml_load(path.read_text(encoding="utf-8"))))
+        pr = _load_or_skip(path, Proposal, "proposal")
+        if pr is not None:
+            out.append(pr)
     return out
 
 

tests/test_stats.py

@@ -97,6 +97,20 @@ def test_review_summary_counts_decisions(store: KBStore) -> None:
     assert review["by_agent"]["a2"]["rejected"] == 1
 
 
+def test_review_summary_skips_corrupt_decided_file(store: KBStore) -> None:
+    """One bad decided/*.yaml must not crash vouch stats / kb.stats."""
+    src = store.put_source(b"x")
+    pr = propose_claim(store, text="ok", evidence=[src.id], proposed_by="a")
+    approve(store, pr.id, approved_by="human")
+    (store.kb_dir / "decided" / "corrupt.yaml").write_text(
+        "not: [valid\n", encoding="utf-8",
+    )
+    review = stats.review_summary(store, since_days=None)
+    assert review["approved"] == 1
+    body = stats.collect_stats(store, since_days=None)
+    assert body["review"]["approved"] == 1
+
+
 def test_review_summary_respects_window(store: KBStore) -> None:
     src = store.put_source(b"x")
     pr = propose_claim(store, text="old", evidence=[src.id], proposed_by="a")