fix: clarify reconciliation and preserve container image tags

main_test.go

@@ -171,3 +171,88 @@ func TestRunPrintsUsageWithoutCommand(t *testing.T) {
 		t.Fatal("missing usage output")
 	}
 }
+
+// TestParseDiagnosisArgsAcceptsService 验证 status/doctor/reconcile 子命令能接受 backend 服务，
+// 且 reconcile 能接受 --apply。
+func TestParseDiagnosisArgsAcceptsService(t *testing.T) {
+	for _, command := range []string{"status", "doctor", "reconcile"} {
+		request, err := parseDiagnosisArgs(command, []string{"--service", "backend"}, &bytes.Buffer{})
+		if err != nil {
+			t.Fatalf("parse %s arguments: %v", command, err)
+		}
+		if request.service != serviceBackend {
+			t.Fatalf("unexpected %s service: %+v", command, request)
+		}
+	}
+	request, err := parseDiagnosisArgs("reconcile", []string{"--service", "backend", "--apply"}, &bytes.Buffer{})
+	if err != nil {
+		t.Fatalf("parse reconcile apply arguments: %v", err)
+	}
+	if !request.apply {
+		t.Fatal("reconcile --apply was not retained")
+	}
+}
+
+// TestParseDiagnosisArgsRejectsUnsupportedInput 验证诊断子命令拒绝缺失服务、
+// 非 backend 服务、位置参数以及非 reconcile 命令使用 --apply。
+func TestParseDiagnosisArgsRejectsUnsupportedInput(t *testing.T) {
+	for name, test := range map[string]struct {
+		command   string
+		arguments []string
+	}{
+		"missing service": {"status", nil},
+		"other service":   {"doctor", []string{"--service", "frontend"}},
+		"positional":      {"status", []string{"--service", "backend", "extra"}},
+		"apply on status": {"status", []string{"--service", "backend", "--apply"}},
+		"apply on doctor": {"doctor", []string{"--service", "backend", "--apply"}},
+	} {
+		t.Run(name, func(t *testing.T) {
+			if _, err := parseDiagnosisArgs(test.command, test.arguments, &bytes.Buffer{}); err == nil {
+				t.Fatal("expected diagnosis argument rejection")
+			}
+		})
+	}
+}
+
+// TestWriteDiagnosisFiltersByCommand 验证 writeDiagnosis 按子命令过滤诊断项：
+// status 只展示漂移与可修复项，doctor 展示全部，reconcile 只展示可修复项。
+func TestWriteDiagnosisFiltersByCommand(t *testing.T) {
+	diagnosis := daemonapi.Diagnosis{
+		Service: "backend",
+		Type:    "container",
+		Healthy: true,
+		Items: []daemonapi.DiagnosisItem{
+			{Level: daemonapi.DiagnosisLevelOK, Code: "active", Message: "活动容器健康"},
+			{Level: daemonapi.DiagnosisLevelFixable, Code: "nginx", Message: "Nginx 指向错误", Action: "切流到 8080"},
+		},
+	}
+
+	var statusOut, doctorOut, reconcileOut bytes.Buffer
+	writeDiagnosis(&statusOut, "status", diagnosis)
+	writeDiagnosis(&doctorOut, "doctor", diagnosis)
+	writeDiagnosis(&reconcileOut, "reconcile", diagnosis)
+
+	if !strings.Contains(statusOut.String(), "Nginx 指向错误") || strings.Contains(statusOut.String(), "活动容器健康") {
+		t.Fatalf("status should hide ok items: %q", statusOut.String())
+	}
+	if !strings.Contains(doctorOut.String(), "活动容器健康") || !strings.Contains(doctorOut.String(), "Nginx 指向错误") {
+		t.Fatalf("doctor should show all items: %q", doctorOut.String())
+	}
+	if !strings.Contains(reconcileOut.String(), "Nginx 指向错误") || strings.Contains(reconcileOut.String(), "活动容器健康") {
+		t.Fatalf("reconcile should only show fixable items: %q", reconcileOut.String())
+	}
+	if !strings.Contains(statusOut.String(), "status=REPAIRABLE") {
+		t.Fatalf("status should distinguish fixable drift: %q", statusOut.String())
+	}
+	if !strings.Contains(reconcileOut.String(), "未执行") || !strings.Contains(reconcileOut.String(), "--apply") {
+		t.Fatalf("reconcile plan should explain that no fix was applied: %q", reconcileOut.String())
+	}
+
+	var appliedOut bytes.Buffer
+	diagnosis.RepairApplied = true
+	diagnosis.RepairTransactionID = "TX-1"
+	writeDiagnosis(&appliedOut, "reconcile", diagnosis)
+	if !strings.Contains(appliedOut.String(), "APPLIED") || !strings.Contains(appliedOut.String(), "TX-1") {
+		t.Fatalf("reconcile apply should show transaction: %q", appliedOut.String())
+	}
+}