[ios] Ensure route settlement on iOS before handling DNS responses (#5360)

* Ensure route settlement on iOS before handling DNS responses to prevent bypassing the tunnel.

* add more logs

* rollback debug changes

* rollback  changes

* [client] Improve logging and add comments for iOS route settlement logic

- Switch iOS route settlement log level from Debug to Trace for finer control.
- Add clarifying comments for `waitForRouteSettlement` on non-iOS platforms.

---------

Co-authored-by: mlsmaycon <mlsmaycon@gmail.com>

client/internal/routemanager/dnsinterceptor/handler_nonios.go

@@ -0,0 +1,12 @@
+//go:build !ios
+
+package dnsinterceptor
+
+import log "github.com/sirupsen/logrus"
+
+func waitForRouteSettlement(_ *log.Entry) {
+	// No-op on non-iOS platforms: route changes are applied synchronously by
+	// the kernel, so no settlement delay is needed before the DNS response
+	// reaches the application. The delay is only required on iOS where
+	// setTunnelNetworkSettings applies routes asynchronously.
+}