agent: keep adaptive rate changes apart from the logs and report them in the heartbeat

backend/shared/MoShiro.Measurement/Blocks/BlockBase.cs

@@ -97,6 +97,20 @@ public abstract class BlockBase : IBlock
 
     private void LogTransition(ProbeTransition change)
     {
+        Env.OnRateChange?.Invoke(new RateChange
+        {
+            AtMs = Env.Time.GetUtcNow().ToUnixTimeMilliseconds(),
+            Task = Spec.Scope.Task?.Value,
+            Kind = Spec.KindId,
+            From = change.From.ToString().ToLowerInvariant(),
+            To = change.To.ToString().ToLowerInvariant(),
+            Hz = Math.Round(change.Hz, 3),
+            Reason = change.Reason,
+            LossPct = Math.Round(change.LossPct, 4),
+            Sent = change.Sent,
+            Lost = change.Lost,
+        });
+
         var fields = new (string, object?)[]
         {
             ("stream", Spec.StreamId), ("kind", Spec.KindId), ("from", change.From.ToString().ToLowerInvariant()), ("to", change.To.ToString().ToLowerInvariant()), ("hz", Math.Round(change.Hz, 1)),

backend/shared/MoShiro.Measurement/Core/Contracts.cs

@@ -245,6 +245,9 @@ public sealed class BlockEnv
     /// <summary>单个 Agent 任务：解析出来的地址能不能连（本地 <c>allowed_target_cidrs</c>）；null 表示不限制。</summary>
     public Func<IPAddress, bool>? AllowAddress { get; init; }
 
+    /// <summary>自适应频率的状态变化（用于审计）；null 表示不记录。</summary>
+    public Action<RateChange>? OnRateChange { get; init; }
+
     /// <summary>拨号方：对端 TLS 证书的 SPKI 指纹；null 表示不校验证书（目标任务，目标是任意地址）。</summary>
     public byte[]? PeerSpkiSha256 { get; init; }
 
@@ -277,6 +280,7 @@ public sealed class BlockEnv
             PeerAddress = PeerAddress,
             Target = Target,
             AllowAddress = AllowAddress,
+            OnRateChange = OnRateChange,
             PeerSpkiSha256 = PeerSpkiSha256,
             KnockKey = KnockKey,
             Fragments = Fragments,