feat!: probes link to the panel; signed release updates for container nodes [CI]

Probes connect to the panel directly and get the agent list as desired state.
CI signs the image digest of agent and probe releases, the panel forwards the
manifest, and a host updater verifies it with a local public key, pulls by
digest and rolls back when the new version is unhealthy.

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()
     {