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/ProbeEndToEndTests.cs

@@ -19,13 +19,13 @@ public sealed class ProbeEndToEndTests
         (await _backend.GetJsonAsync(_backend.Admin, $"/api/admin/raw/chunks?agent_id={agent.Id}"))["items"]!.AsArray().Count(c => c!["kind"]!.GetValue<string>() == kind);
 
     [Fact]
-    public async Task Probe_ConnectsThroughTheBootstrapList_RunsTheLineTasks_AndTheBackendStoresMergedChunks()
+    public async Task Probe_GetsTheAgentListFromThePanel_RunsTheLineTasks_AndTheBackendStoresMergedChunks()
     {
         await using AgentHarness agent = await AgentHarness.StartAsync(_backend);
         await agent.OverrideLineTasksAsync(rateHz: 30);
         await using ProbeHarness probe = await ProbeHarness.StartAsync(_backend);
 
-        await BackendFixture.EventuallyAsync(() => Task.FromResult(probe.App.IsConnected(agent.Id)), because: "the probe should connect to the bootstrap agent");
+        await BackendFixture.EventuallyAsync(() => Task.FromResult(probe.App.IsConnected(agent.Id)), because: "the panel sends the agent list to the probe, which then connects");
         await BackendFixture.EventuallyAsync(async () => (await AgentViewAsync(agent))["probe_connected"]!.GetValue<bool>());
         await BackendFixture.EventuallyAsync(() => Task.FromResult(probe.App.Connection(agent.Id)!.RoleCount == 2), because: "udp_echo and tcp_echo");
 
@@ -38,6 +38,26 @@ public sealed class ProbeEndToEndTests
         Assert.InRange(probe.App.Connection(agent.Id)!.ClockOffsetUs, -20_000, 20_000);
     }
 
+    [Fact]
+    public async Task Probe_IntroducesItselfToThePanel_AndARevokedProbeIsLockedOut()
+    {
+        await _backend.SiteMustBePublicAsync();
+        await using ProbeHarness probe = await ProbeHarness.StartAsync(_backend);
+        string path = "/api/admin/probes/" + probe.ProbeId;
+
+        // 直连面板：在线，hello 里的系统、架构和版本都被记下来了
+        await BackendFixture.EventuallyAsync(async () => (await _backend.GetJsonAsync(_backend.Admin, path))["online"]!.GetValue<bool>(), because: "the probe links to the panel");
+        await BackendFixture.EventuallyAsync(
+            async () => (await _backend.GetJsonAsync(_backend.Anonymous, "/api/public/nodes"))["items"]!.AsArray().Any(n => n!["id"]!.GetValue<string>() == probe.ProbeId && n["os"] is not null && n["arch"] is not null),
+            because: "the platform comes from the probe's own hello");
+
+        // 吊销：面板立刻断开它，之后连不上
+        using HttpResponseMessage revoked = await _backend.Admin.PostAsync(path + "/revoke", null);
+        revoked.EnsureSuccessStatusCode();
+        await BackendFixture.EventuallyAsync(async () => !(await _backend.GetJsonAsync(_backend.Admin, path))["online"]!.GetValue<bool>(), because: "a revoked probe is disconnected and cannot come back");
+        Assert.False(probe.App.Link.IsConnected);
+    }
+
     [Fact]
     public async Task Probe_FollowsTheAgentListThePanelKnows_AndSavesItForTheNextStart()
     {