fix(alerting/I-1): retry endpoint resets attempts to 0 instead of incrementing

AlertNotificationRepository gains resetForRetry(UUID, Instant) which sets
attempts=0, status=PENDING, next_attempt_at=now, and clears claim/response
fields. AlertNotificationController calls resetForRetry instead of
scheduleRetry so a manual retry always starts from a clean slate.

AlertNotificationControllerIT adds retryResetsAttemptsToZero to verify
attempts==0 and status==PENDING after three prior markFailed calls.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cameleer-server-app/src/main/java/com/cameleer/server/app/alerting/controller/AlertNotificationController.java

@@ -69,10 +69,7 @@ public class AlertNotificationController {
         }
 
         // Reset for retry: status -> PENDING, attempts -> 0, next_attempt_at -> now
-        // We use scheduleRetry to reset attempt timing; then we need to reset attempts count.
-        // The repository has scheduleRetry which sets next_attempt_at and records last status.
-        // We use a dedicated pattern: mark as pending by scheduling immediately.
-        notificationRepo.scheduleRetry(id, Instant.now(), 0, null);
+        notificationRepo.resetForRetry(id, Instant.now());
 
         return AlertNotificationDto.from(notificationRepo.findById(id)
                 .orElseThrow(() -> new ResponseStatusException(HttpStatus.NOT_FOUND)));

cameleer-server-app/src/main/java/com/cameleer/server/app/alerting/storage/PostgresAlertNotificationRepository.java

@@ -118,6 +118,21 @@ public class PostgresAlertNotificationRepository implements AlertNotificationRep
             """, Timestamp.from(nextAttemptAt), status, snippet, id);
     }
 
+    @Override
+    public void resetForRetry(UUID id, Instant nextAttemptAt) {
+        jdbc.update("""
+            UPDATE alert_notifications
+               SET attempts              = 0,
+                   status               = 'PENDING'::notification_status_enum,
+                   next_attempt_at      = ?,
+                   claimed_by           = NULL,
+                   claimed_until        = NULL,
+                   last_response_status = NULL,
+                   last_response_snippet = NULL
+             WHERE id = ?
+            """, Timestamp.from(nextAttemptAt), id);
+    }
+
     @Override
     public void markFailed(UUID id, int status, String snippet) {
         jdbc.update("""

cameleer-server-app/src/test/java/com/cameleer/server/app/alerting/controller/AlertNotificationControllerIT.java

@@ -113,6 +113,35 @@ class AlertNotificationControllerIT extends AbstractPostgresIT {
         assertThat(resp.getStatusCode()).isEqualTo(HttpStatus.OK);
     }
 
+    @Test
+    void retryResetsAttemptsToZero() throws Exception {
+        // Verify Fix I-1: retry endpoint resets attempts to 0, not attempts+1
+        AlertInstance instance = seedInstance();
+        AlertNotification notification = seedNotification(instance.id());
+
+        // Mark as failed with attempts at max (simulate exhausted retries)
+        notificationRepo.markFailed(notification.id(), 500, "server error");
+        notificationRepo.markFailed(notification.id(), 500, "server error");
+        notificationRepo.markFailed(notification.id(), 500, "server error");
+
+        // Verify attempts > 0 before retry
+        AlertNotification before = notificationRepo.findById(notification.id()).orElseThrow();
+        assertThat(before.attempts()).isGreaterThan(0);
+
+        // Operator retries
+        ResponseEntity<String> resp = restTemplate.exchange(
+                "/api/v1/alerts/notifications/" + notification.id() + "/retry",
+                HttpMethod.POST,
+                new HttpEntity<>(securityHelper.authHeaders(operatorJwt)),
+                String.class);
+        assertThat(resp.getStatusCode()).isEqualTo(HttpStatus.OK);
+
+        // After retry: attempts must be 0 and status PENDING (not attempts+1)
+        AlertNotification after = notificationRepo.findById(notification.id()).orElseThrow();
+        assertThat(after.attempts()).as("retry must reset attempts to 0").isEqualTo(0);
+        assertThat(after.status()).isEqualTo(NotificationStatus.PENDING);
+    }
+
     @Test
     void viewerCannotRetry() throws Exception {
         AlertInstance instance = seedInstance();

cameleer-server-core/src/main/java/com/cameleer/server/core/alerting/AlertNotificationRepository.java

@@ -13,5 +13,7 @@ public interface AlertNotificationRepository {
     void markDelivered(UUID id, int status, String snippet, Instant when);
     void scheduleRetry(UUID id, Instant nextAttemptAt, int status, String snippet);
     void markFailed(UUID id, int status, String snippet);
+    /** Resets a FAILED notification for operator-triggered retry: attempts → 0, status → PENDING. */
+    void resetForRetry(UUID id, Instant nextAttemptAt);
     void deleteSettledBefore(Instant cutoff);
 }