fix(moderation): policy list viewer reads legacy Draupnir/Mjolnir rule types

Only the stable m.policy.rule.* types were queried, so lists still writing
org.matrix.mjolnir.rule.* showed as empty. Query both and de-duplicate by
entity+recommendation.

Fixes #22

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

src/app/features/room-settings/PolicyListViewer.tsx

@@ -24,6 +24,14 @@ const POLICY_USER_EVENT = 'm.policy.rule.user';
 const POLICY_ROOM_EVENT = 'm.policy.rule.room';
 const POLICY_SERVER_EVENT = 'm.policy.rule.server';
 
+// Legacy, unstable-prefixed event types still emitted by Draupnir/Mjolnir
+// policy lists that predate MSC stabilization (or haven't migrated). Queried
+// alongside the stable types and merged/de-duped so those lists don't show
+// as falsely empty.
+const LEGACY_POLICY_USER_EVENT = 'org.matrix.mjolnir.rule.user';
+const LEGACY_POLICY_ROOM_EVENT = 'org.matrix.mjolnir.rule.room';
+const LEGACY_POLICY_SERVER_EVENT = 'org.matrix.mjolnir.rule.server';
+
 type PolicyRuleContent = {
   entity?: string;
   reason?: string;
@@ -76,6 +84,23 @@ function extractPolicyEntries(events: MatrixEvent[]): PolicyEntry[] {
     .filter((entry) => entry.entity !== '');
 }
 
+/**
+ * Merge policy entries from the stable and legacy event types for a rule
+ * kind, de-duplicating by entity+recommendation so a room that emits both a
+ * stable and a legacy rule for the same target isn't double-listed.
+ */
+export function dedupePolicyEntries(entries: PolicyEntry[]): PolicyEntry[] {
+  const seen = new Set<string>();
+  const result: PolicyEntry[] = [];
+  entries.forEach((entry) => {
+    const key = `${entry.entity} ${entry.recommendation}`;
+    if (seen.has(key)) return;
+    seen.add(key);
+    result.push(entry);
+  });
+  return result;
+}
+
 // ── Entry row ─────────────────────────────────────────────────────────────────
 
 function PolicyEntryRow({ entry }: { entry: PolicyEntry }) {
@@ -201,9 +226,24 @@ export function PolicyListViewer({ requestClose }: PolicyListViewerProps) {
       return;
     }
 
-    setUserEntries(extractPolicyEntries(getRoomPolicyEvents(room, POLICY_USER_EVENT)));
-    setRoomEntries(extractPolicyEntries(getRoomPolicyEvents(room, POLICY_ROOM_EVENT)));
-    setServerEntries(extractPolicyEntries(getRoomPolicyEvents(room, POLICY_SERVER_EVENT)));
+    setUserEntries(
+      dedupePolicyEntries([
+        ...extractPolicyEntries(getRoomPolicyEvents(room, POLICY_USER_EVENT)),
+        ...extractPolicyEntries(getRoomPolicyEvents(room, LEGACY_POLICY_USER_EVENT)),
+      ]),
+    );
+    setRoomEntries(
+      dedupePolicyEntries([
+        ...extractPolicyEntries(getRoomPolicyEvents(room, POLICY_ROOM_EVENT)),
+        ...extractPolicyEntries(getRoomPolicyEvents(room, LEGACY_POLICY_ROOM_EVENT)),
+      ]),
+    );
+    setServerEntries(
+      dedupePolicyEntries([
+        ...extractPolicyEntries(getRoomPolicyEvents(room, POLICY_SERVER_EVENT)),
+        ...extractPolicyEntries(getRoomPolicyEvents(room, LEGACY_POLICY_SERVER_EVENT)),
+      ]),
+    );
     setLoadedRoomId(roomId);
     setError(undefined);
   }, [mx, roomIdInput]);