preserve failure count on service recovery in incident header

Recovered services are now shown as ':large_green_circle: <name> (<count>)'
with the last failure count that was observed before the service recovered,
matching the red-circle format.

monitoring/src/main/java/org/thingsboard/monitoring/notification/incident/IncidentManager.java

@@ -51,7 +51,7 @@ public class IncidentManager {
     private Instant incidentStartTime;
     private Instant lastAlertTime;
     private final Map<String, Integer> failingServices = new LinkedHashMap<>();
-    private final Set<String> recoveredServices = new LinkedHashSet<>();
+    private final Map<String, Integer> recoveredServices = new LinkedHashMap<>();
     private final Set<String> highLatencyServices = new LinkedHashSet<>();
 
     public IncidentManager(IncidentTransport transport, long resolutionTimeoutSeconds,
@@ -110,13 +110,14 @@ public class IncidentManager {
                     if (prev == null || prev.intValue() != service.failureCount()) {
                         changed = true;
                     }
-                    if (recoveredServices.remove(name)) {
+                    if (recoveredServices.remove(name) != null) {
                         changed = true;
                     }
                 }
                 case RECOVERED -> {
-                    if (failingServices.remove(name) != null) {
-                        recoveredServices.add(name);
+                    Integer lastFailureCount = failingServices.remove(name);
+                    if (lastFailureCount != null) {
+                        recoveredServices.put(name, lastFailureCount);
                         changed = true;
                     }
                 }
@@ -257,9 +258,9 @@ public class IncidentManager {
             sb.append(":large_yellow_circle: ").append(name);
             first = false;
         }
-        for (String name : recoveredServices) {
+        for (Map.Entry<String, Integer> entry : recoveredServices.entrySet()) {
             if (!first) sb.append(", ");
-            sb.append(":large_green_circle: ").append(name);
+            sb.append(":large_green_circle: ").append(entry.getKey()).append(" (").append(entry.getValue()).append(")");
             first = false;
         }
         return sb.toString();

monitoring/src/test/java/org/thingsboard/monitoring/notification/incident/IncidentManagerTest.java

@@ -85,13 +85,13 @@ class IncidentManagerTest {
     }
 
     @Test
-    void recoveryAfterFailureMovesServiceToGreenAndUpdatesHeader() {
-        manager.sendAlert("CoAP failure", List.of(AffectedService.failing("CoAP", 1)));
+    void recoveryAfterFailureMovesServiceToGreenAndKeepsFailureCount() {
+        manager.sendAlert("CoAP failure", List.of(AffectedService.failing("CoAP", 4)));
         manager.sendAlert("CoAP is OK", List.of(AffectedService.recovered("CoAP")));
 
         assertThat(transport.updates).hasSize(1);
         String updated = transport.updates.get(0).text();
-        assertThat(updated).contains(":large_green_circle: CoAP").doesNotContain(":red_circle:");
+        assertThat(updated).contains(":large_green_circle: CoAP (4)").doesNotContain(":red_circle:");
     }
 
     @Test
@@ -126,7 +126,7 @@ class IncidentManagerTest {
                 .asString()
                 .contains(":white_check_mark:")
                 .contains(":red_circle: WS Connect")
-                .contains(":large_green_circle: Login");
+                .contains(":large_green_circle: Login (1)");
     }
 
     @Test