cmd/cli: add split route AD top level domain on Windows

The sub-domains are matched using wildcard domain rule, but this rule
won't match top level domain, causing requests are forwarded to ControlD
upstreams.

To fix this, add the split route for top level domain explicitly.

cmd/cli/ad_windows_test.go

@@ -4,6 +4,10 @@ import (
 	"fmt"
 	"testing"
 	"time"
+
+	"github.com/Control-D-Inc/ctrld"
+	"github.com/Control-D-Inc/ctrld/testhelper"
+	"github.com/stretchr/testify/assert"
 )
 
 func Test_getActiveDirectoryDomain(t *testing.T) {
@@ -34,3 +38,35 @@ func getActiveDirectoryDomainPowershell() (string, error) {
 	}
 	return string(output), nil
 }
+
+func Test_addSplitDnsRule(t *testing.T) {
+	newCfg := func(domains ...string) *ctrld.Config {
+		cfg := testhelper.SampleConfig(t)
+		lc := cfg.Listener["0"]
+		for _, domain := range domains {
+			lc.Policy.Rules = append(lc.Policy.Rules, ctrld.Rule{domain: []string{}})
+		}
+		return cfg
+	}
+	tests := []struct {
+		name   string
+		cfg    *ctrld.Config
+		domain string
+		added  bool
+	}{
+		{"added", newCfg(), "example.com", true},
+		{"TLD existed", newCfg("example.com"), "*.example.com", true},
+		{"wildcard existed", newCfg("*.example.com"), "example.com", true},
+		{"not added TLD", newCfg("example.com", "*.example.com"), "example.com", false},
+		{"not added wildcard", newCfg("example.com", "*.example.com"), "*.example.com", false},
+	}
+
+	for _, tc := range tests {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			added := addSplitDnsRule(tc.cfg, tc.domain)
+			assert.Equal(t, tc.added, added)
+		})
+	}
+}