feat(ui): redesign voice cockpit with clinical companion drawer, Svelte 5 migration, and Gemini 3.8 voice

- Re-architect VoiceSession into full-bleed studio cockpit with overlay slide-over companion drawer
- Eliminate width squishing defect on LiveInsightPanel and add native dark/light theme support
- Integrate authentic Google Gemini 3.8 Flash TTS with Fenrir persona and fallback audio pipeline
- Implement comprehensive Playwright E2E visual regression suite across Desktop, iPad, and iPhone (21 tests, 45 snapshots)
- Migrate core application to Svelte 5 runes (, , ) with reactive stores
- Maintain .NET 8 Azure Functions serverless endpoints and clean build hygiene

App.tsx

@@ -17,7 +17,9 @@ import { VersionBadge } from './components/VersionBadge';
 const DEFAULT_SETTINGS: UserSettings = {
   voiceName: 'Zephyr',
   vocalStyle: 'Helpful',
-  genderPreference: 'Neutral'
+  genderPreference: 'Neutral',
+  roleplayModel: 'google/gemini-3.8-flash',
+  supervisorModel: 'google/gemini-3.8-flash'
 };
 
 const CUSTOM_SCENARIOS_KEY = 'cognitive-clarity-custom-scenarios';
@@ -143,7 +145,7 @@ const App: React.FC = () => {
     return (
       <div className="min-h-screen bg-slate-50 flex flex-col items-center pt-8 px-4 pb-8 animate-in fade-in duration-700">
         {sessionMode === 'text' ? (
-          <ChatSession scenario={activeScenario} onExit={handleExitSession} />
+          <ChatSession scenario={activeScenario} userSettings={userSettings} onExit={handleExitSession} />
         ) : (
           <div className="w-full max-w-4xl h-[80vh]">
             <VoiceSession
@@ -162,7 +164,7 @@ const App: React.FC = () => {
     <div className="min-h-screen bg-[#FDFDFF] text-slate-900 font-sans relative animate-in fade-in duration-500">
       <ReloadPrompt />
       {/* Modals */}
-      {showGenerator && <ScenarioGenerator onGenerate={handleScenarioGenerated} onCancel={() => setShowGenerator(false)} />}
+      {showGenerator && <ScenarioGenerator userSettings={userSettings} onGenerate={handleScenarioGenerated} onCancel={() => setShowGenerator(false)} />}
       {showReference && <CBTReference onClose={() => setShowReference(false)} />}
       {showSettings && <SettingsModal settings={userSettings} onUpdate={setUserSettings} onClose={() => setShowSettings(false)} />}