Add minimal sensitive-info hygiene plan and projection cause sample diagnostics

artifacts/plans/14-sensitive-info-hygiene.md

@@ -0,0 +1,9 @@
+# 14) Sensitive Information Hygiene
+
+## Goal
+Detect and remove sensitive data exposure from code, config, logs, and payload surfaces.
+
+## Minimal Plan
+1. Add a repeatable scan for sensitive patterns across repo and runtime-generated artifacts.
+2. Expunge discovered sensitive values and replace with safe placeholders or references.
+3. Add guardrails to prevent reintroduction and document the remediation workflow.

core/events/projection.py

@@ -179,15 +179,19 @@ def shadow_compare_session(session: ChatSession, detail_limit: int = 50) -> dict
         "ambiguous_reaction_target": 0,
         "payload_normalization_gap": 0,
     }
+    cause_samples = {key: [] for key in cause_counts.keys()}
+    cause_sample_limit = min(5, max(0, int(detail_limit)))
 
     def _record_detail(message_id: str, issue: str, cause: str, extra: dict | None = None):
         if cause in cause_counts:
             cause_counts[cause] += 1
-        if len(details) < max(0, int(detail_limit)):
         row = {"message_id": message_id, "issue": issue, "cause": cause}
         if extra:
             row.update(dict(extra))
+        if len(details) < max(0, int(detail_limit)):
             details.append(row)
+        if cause in cause_samples and len(cause_samples[cause]) < cause_sample_limit:
+            cause_samples[cause].append(row)
 
     for message_id, db_row in db_by_id.items():
         projected = projected_by_id.get(message_id)
@@ -289,5 +293,6 @@ def shadow_compare_session(session: ChatSession, detail_limit: int = 50) -> dict
         "mismatch_total": mismatch_total,
         "counters": counters,
         "cause_counts": cause_counts,
+        "cause_samples": cause_samples,
         "details": details,
     }

core/tests/test_event_projection_shadow.py

@@ -96,6 +96,12 @@ class EventProjectionShadowTests(TestCase):
         )
         compared = shadow_compare_session(self.session, detail_limit=10)
         self.assertGreater(compared["counters"]["missing_in_projection"], 0)
+        self.assertIn("cause_samples", compared)
+        self.assertIn("missing_event_write", compared["cause_samples"])
+        self.assertGreaterEqual(
+            len(compared["cause_samples"]["missing_event_write"]),
+            1,
+        )
 
     def test_management_command_emits_summary(self):
         out = StringIO()

core/views/system.py

@@ -257,5 +257,6 @@ class EventProjectionShadowAPI(SuperUserRequiredMixin, View):
                 "ok": True,
                 "result": compared,
                 "cause_summary": dict(compared.get("cause_counts") or {}),
+                "cause_samples": dict(compared.get("cause_samples") or {}),
             }
         )