fix: clarify shadow refresh recovery contract

ruoyi-admin/src/main/java/com/ruoyi/algorithm/shadow/ShadowSnapshotCoordinator.java

@@ -2,6 +2,7 @@ package com.ruoyi.algorithm.shadow;
 
 import java.time.Duration;
 import java.time.Instant;
+import java.time.Clock;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -17,6 +18,7 @@ public final class ShadowSnapshotCoordinator {
 
     private final String configuredWarehouseId;
     private final Duration snapshotMaxAge;
+    private final Clock clock;
     private final AtomicReference<State> state = new AtomicReference<>(
             new State(Phase.INITIALIZING, 0L, 0, null, null, null, null));
 
@@ -25,8 +27,13 @@ public final class ShadowSnapshotCoordinator {
     }
 
     public ShadowSnapshotCoordinator(String configuredWarehouseId, Duration snapshotMaxAge) {
+        this(configuredWarehouseId, snapshotMaxAge, Clock.systemUTC());
+    }
+
+    public ShadowSnapshotCoordinator(String configuredWarehouseId, Duration snapshotMaxAge, Clock clock) {
         this.configuredWarehouseId = Objects.requireNonNull(configuredWarehouseId, "configuredWarehouseId").trim();
         this.snapshotMaxAge = Objects.requireNonNull(snapshotMaxAge, "snapshotMaxAge");
+        this.clock = Objects.requireNonNull(clock, "clock");
         if (snapshotMaxAge.isNegative() || snapshotMaxAge.isZero()) {
             throw new IllegalArgumentException("snapshotMaxAge must be positive");
         }
@@ -85,7 +92,7 @@ public final class ShadowSnapshotCoordinator {
                 return;
             }
             int nextActiveCount = current.activeLegacyCount() - 1;
-            Instant nextQuietSince = nextActiveCount == 0 ? Instant.now() : current.quietSince();
+            Instant nextQuietSince = nextActiveCount == 0 ? clock.instant() : current.quietSince();
             State next = new State(current.phase(), current.epoch(), nextActiveCount, current.published(),
                     current.leasedEpoch(), nextQuietSince, current.lastFailure());
             if (state.compareAndSet(current, next)) {