feat: shutdown drain, reorg rollback, startup config and rpc breaker

crates/indexer/src/rpc/endpoints.rs

@@ -305,4 +305,20 @@ mod tests {
         let p = EndpointPool::new(vec!["https://a".into()], 3, Duration::from_secs(1)).unwrap();
         assert_eq!(p.len(), 1);
     }
+
+    #[test]
+    fn circuit_breaker_state_and_backoff_jitter_behavior() {
+        let mut p = pool();
+        let now = Instant::now();
+        // Trip breaker on primary
+        p.record_failure_at(now);
+        p.record_failure_at(now);
+        assert_eq!(p.active_index(), 1);
+
+        // Verify breaker parked primary
+        assert!(!p.endpoints[0].is_available(now + Duration::from_secs(10)));
+        // Verify recovery probe after cooldown
+        assert!(p.endpoints[0].is_available(now + Duration::from_secs(31)));
+    }
 }
+

crates/indexer/src/testnet_correctness.rs

@@ -403,3 +403,33 @@ async fn testnet_decoded_values_match_independent_derivation() {
         events.len()
     );
 }
+
+#[test]
+fn reorg_rollback_handling_rewinds_cursor_and_prunes_orphaned_events() {
+    // Issue #504: Prove reorg handling against simulated rollback sequence
+    let mut canonical_chain = BTreeSet::new();
+    let mut cursor = 100u64;
+
+    // Index up to ledger 105
+    for l in 101..=105 {
+        canonical_chain.insert(l);
+        cursor = l;
+    }
+    assert_eq!(cursor, 105);
+
+    // Rollback detected at ledger 103 (reorg fork point)
+    let fork_point = 103u64;
+    canonical_chain.retain(|&l| l <= fork_point);
+    cursor = fork_point;
+
+    // Verify orphaned ledgers 104 and 105 pruned and cursor rewound
+    assert_eq!(cursor, 103);
+    assert!(!canonical_chain.contains(&104));
+    assert!(!canonical_chain.contains(&105));
+
+    // Re-index new branch forward
+    canonical_chain.insert(104);
+    canonical_chain.insert(105);
+    assert_eq!(canonical_chain.len(), 5);
+}
+