fix(setup): say when a URL was rejected rather than blaming telnet

Adding urls.validate() to setAllBoseURLsViaTelnet made a rejected URL come
back through resyncBoseURLsAfterXML as "could not re-sync boseurls over
telnet", which reads as the device being unreachable and sends the user to
look at port 17000.

applyURLOverrides lets the XML migration accept URLs the telnet validator now
refuses, a query string for instance, so this is reachable: the XML write
succeeds with that value while the runtime re-sync is silently skipped. A
reboot does reconcile from the XML, so the outcome is fine; the diagnosis was
not.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

pkg/service/setup/setup.go

@@ -1178,6 +1178,14 @@ func (m *Manager) resyncBoseURLsAfterXML(deviceIP string, urls telnetURLs) strin
 
 	rlogs, rerr := m.setAllBoseURLsViaTelnet(deviceIP, urls)
 	if rerr != nil {
+		// A rejected URL is not the device being unreachable, and saying so
+		// would send the user looking at telnet. The XML write has already
+		// happened with this value, so the URL itself is what needs attention.
+		if errors.Is(rerr, ErrInvalidTelnetURL) {
+			return fmt.Sprintf("Note: skipped the telnet boseurls re-sync because a URL was rejected (%v); "+
+				"the XML configuration was still written, and a device reboot will reconcile the runtime layer.\n", rerr)
+		}
+
 		return fmt.Sprintf("Note: could not re-sync boseurls over telnet (%v); a device reboot will reconcile the runtime layer.\n", rerr)
 	}
 

pkg/service/setup/telnet_migration_test.go

@@ -543,3 +543,25 @@ func TestMigrateViaTelnet_FailureReportsWhatTheDeviceHolds(t *testing.T) {
 		t.Errorf("logs did not record the read-back:\n%s", logs)
 	}
 }
+
+// TestResyncBoseURLsAfterXML_DistinguishesRejectedURL: applyURLOverrides lets
+// the XML path accept URLs the telnet validator refuses, so the XML write
+// succeeds while the re-sync is skipped. Reporting that as "could not re-sync
+// over telnet" points the user at the wrong thing.
+func TestResyncBoseURLsAfterXML_DistinguishesRejectedURL(t *testing.T) {
+	m := newFakeTelnetManager(&fakeTelnet{responses: map[string]string{}})
+
+	rejected := m.resyncBoseURLsAfterXML("192.0.2.1", telnetURLs{
+		Marge:       "http://example:8000?probe=1",
+		Stats:       "http://example:8000",
+		SwUpdate:    "http://example:8000/updates/soundtouch",
+		BmxRegistry: "http://example:8000/bmx/registry/v1/services",
+	})
+
+	if !strings.Contains(rejected, "a URL was rejected") {
+		t.Errorf("note = %q, want it to name the rejected URL as the cause", rejected)
+	}
+	if strings.Contains(rejected, "could not re-sync boseurls over telnet") {
+		t.Errorf("note = %q, want it not to blame telnet availability", rejected)
+	}
+}