Tighten verbose comments in Wails UI Go code

Shorten over-long godoc/inline comments across the client/ui tray and
services code: drop narrative restatement, legacy-Fyne tangents, and text
already evident from signatures and names. Keep only the non-obvious why
(concurrency/lock ordering, platform quirks, ordering constraints, the
profile-switch state table). No code changes.

client/ui/services/preferences.go

@@ -9,10 +9,8 @@ import (
 	"github.com/netbirdio/netbird/client/ui/preferences"
 )
 
-// Preferences is the Wails-bound facade over preferences.Store. The store
-// itself owns persistence and the subscription channel; this type just
-// re-exposes Get and SetLanguage with the context.Context-first signature
-// the Wails binding generator wants.
+// Preferences is the Wails-bound facade over preferences.Store; the context.Context-first
+// signatures are what the binding generator requires.
 type Preferences struct {
 	store *preferences.Store
 }
@@ -21,23 +19,18 @@ func NewPreferences(store *preferences.Store) *Preferences {
 	return &Preferences{store: store}
 }
 
-// Get returns the current user-scope preferences.
 func (s *Preferences) Get(_ context.Context) (preferences.UIPreferences, error) {
 	return s.store.Get(), nil
 }
 
-// SetLanguage validates and persists a new UI language.
 func (s *Preferences) SetLanguage(_ context.Context, lang i18n.LanguageCode) error {
 	return s.store.SetLanguage(lang)
 }
 
-// SetViewMode validates and persists the Main-window view choice
-// ("default" or "advanced").
 func (s *Preferences) SetViewMode(_ context.Context, mode preferences.ViewMode) error {
 	return s.store.SetViewMode(mode)
 }
 
-// SetOnboardingCompleted persists the welcome-flow dismissal flag.
 func (s *Preferences) SetOnboardingCompleted(_ context.Context, done bool) error {
 	return s.store.SetOnboardingCompleted(done)
 }