feat!: probes connect to the backend directly

A probe now links to the backend like an agent (probe.json carries the
server address). The backend sends the agent list as desired state and the
probe reports its platform and build in its own hello. The agent no longer
relays the list or the probe platform. Existing probes must be re-created.

backend/tests/Monitor.Backend.Tests/EnrollmentAndTaskSetTests.cs

@@ -338,7 +338,7 @@ public sealed class EnrollmentAndTaskSetTests
         JsonNode identity = JsonNode.Parse(await created.Content.ReadAsStringAsync())!;
         string id = identity["probe_id"]!.GetValue<string>();
         using var key1 = Fleet.Identity.NodeIdentity.FromPkcs8(Convert.FromBase64String(identity["private_key"]!.GetValue<string>()));
-        Assert.Contains(identity["bootstrap"]!.AsArray(), b => b!["agent_id"]!.GetValue<string>() == agent.NodeId.Value);
+        Assert.True(Uri.TryCreate(identity["server"]!.GetValue<string>(), UriKind.Absolute, out _)); // Probe 直接连面板：probe.json 里是面板的地址
         await agent.WaitForTaskSetAsync(s => s.Peers.Any(p => p.ProbeId.Value == id && p.PublicKey == Convert.ToBase64String(key1.PublicKeySpki)));
 
         // The panel lists it; two probes can coexist and a duplicate name is refused
@@ -374,34 +374,6 @@ public sealed class EnrollmentAndTaskSetTests
         Assert.Equal(HttpStatusCode.NotFound, gone.StatusCode);
     }
 
-    [Fact]
-    public async Task ProbeAgentList_IsServedToAgents_AndPushedWhenTheSetOfAgentsChanges()
-    {
-        await using AgentSimulator first = await _backend.ConnectAgentAsync();
-        ProbeAgentsResult list = await first.RequestProbeAgentsAsync();
-        Assert.Contains(list.Agents, a => a.AgentId == first.NodeId && a.Host == "203.0.113.10" && a.TcpPort == 7443);
-        Assert.All(list.Agents, a => Assert.Equal(32, Convert.FromBase64String(a.Spki).Length));
-
-        await using AgentSimulator second = await _backend.ConnectAgentAsync();
-        ProbeAgentsResult pushed = await WaitForAsync(first, l => l.Agents.Any(a => a.AgentId == second.NodeId));
-        Assert.True(pushed.Version > list.Version);
-
-        using HttpResponseMessage disable = await _backend.Admin.PostAsync($"/api/admin/agents/{second.NodeId.Value}/disable", null);
-        Assert.Equal(HttpStatusCode.OK, disable.StatusCode);
-        await WaitForAsync(first, l => l.Agents.All(a => a.AgentId != second.NodeId));
-    }
-
-    private static async Task<ProbeAgentsResult> WaitForAsync(AgentSimulator agent, Func<ProbeAgentsResult, bool> predicate)
-    {
-        ProbeAgentsResult? found = null;
-        await BackendFixture.EventuallyAsync(() =>
-        {
-            found = agent.ProbeAgentLists.ToArray().LastOrDefault(predicate);
-            return Task.FromResult(found is not null);
-        });
-        return found!;
-    }
-
     private Task<HttpResponseMessage> PostEnrollAsync(JsonNode body) =>
         _backend.Anonymous.PostAsync("/api/agent/v1/enroll", BackendFixture.Json(body));
 }