[client] UI refactor (#6069)

Refactor UI

---------

Co-authored-by: Eduard Gert <kontakt@eduardgert.de>
Co-authored-by: braginini <bangvalo@gmail.com>
Co-authored-by: Pascal Fischer <32096965+pascal-fischer@users.noreply.github.com>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: riccardom <riccardomanfrin@gmail.com>

client/ui/tray_watcher_other.go

@@ -0,0 +1,9 @@
+//go:build (!linux || (linux && 386)) && !freebsd && !android && !ios && !js
+
+package main
+
+// startStatusNotifierWatcher is a no-op stub so main.go can call it across all
+// build targets; only minimal Linux WMs need the real watcher (tray_watcher_linux.go).
+func startStatusNotifierWatcher() {
+	// Intentionally empty: only minimal Linux WMs need the real SNI watcher.
+}