Don't double-label voices whose name already carries the quality tier

Premium/enhanced voices ship with the tier in their name (e.g. "Ava
(Premium)"), so appending "— Premium" produced "Ava (Premium) — Premium"
in the voice picker. Move the label logic to SpeechSettings.displayLabel
and skip the suffix when the name already contains the tier (still
name-only for default voices). Deterministic string helper, unit-tested.

Claude-Session: https://claude.ai/code/session_01BQcEWmAPA78338QuEwRkAh

Workouts/Views/Settings/SettingsView.swift

@@ -211,14 +211,6 @@ struct SettingsView: View {
         installedVoices.contains { $0.quality != .default }
     }
 
-    /// Most installed voices are default quality, so labeling every one "Default" is noise;
-    /// name only for those, and call out the enhanced/premium ones that are worth choosing.
-    private func voiceLabel(_ voice: AVSpeechSynthesisVoice) -> String {
-        voice.quality == .default
-            ? voice.name
-            : "\(voice.name) — \(SpeechSettings.qualityLabel(voice.quality))"
-    }
-
     /// All spoken-instruction controls. The voice and the speed/pitch/volume adjustments also
     /// govern the library exercise Speak button; only the toggle gates the automatic workout cue.
     @ViewBuilder
@@ -233,7 +225,8 @@ struct SettingsView: View {
             Picker("Voice", selection: $speechVoiceIdentifier) {
                 Text("Automatic").tag("")
                 ForEach(installedVoices, id: \.identifier) { voice in
-                    Text(voiceLabel(voice)).tag(voice.identifier)
+                    Text(SpeechSettings.displayLabel(name: voice.name, quality: voice.quality))
+                        .tag(voice.identifier)
                 }
             }