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

services/apiConfig.ts

@@ -0,0 +1,100 @@
+/**
+ * API Configuration & Key Resolution Service
+ * 
+ * Provides unified, hierarchical access to OpenRouter API credentials,
+ * supporting browser LocalStorage overrides and environment variables.
+ */
+
+import { UserSettings } from '../types';
+
+const SETTINGS_KEY = 'cognitive-clarity-settings';
+
+export const DEFAULT_OPENROUTER_MODEL = 'google/gemini-3.8-flash';
+export const DEFAULT_SUPERVISOR_MODEL = 'google/gemini-3.8-flash';
+
+export function getStoredUserSettings(): Partial<UserSettings> {
+  try {
+    if (typeof localStorage === 'undefined') {
+      return {};
+    }
+    const saved = localStorage.getItem(SETTINGS_KEY);
+    return saved ? JSON.parse(saved) : {};
+  } catch (e) {
+    console.error("Failed to read user settings from localStorage", e);
+    return {};
+  }
+}
+
+/**
+ * Returns the effective OpenRouter API Key.
+ * Precedence:
+ * 1. Explicit argument
+ * 2. UserSettings in LocalStorage
+ * 3. Vite environment variable (VITE_OPENROUTER_API_KEY)
+ * 4. Node process environment variable (OPENROUTER_API_KEY)
+ */
+export function getOpenRouterApiKey(customKey?: string): string {
+  if (customKey !== undefined) {
+    return customKey.trim();
+  }
+
+  const stored = getStoredUserSettings();
+  if (stored.openRouterApiKey && stored.openRouterApiKey.trim().length > 0) {
+    return stored.openRouterApiKey.trim();
+  }
+
+  if (typeof process !== 'undefined' && process.env?.OPENROUTER_API_KEY !== undefined) {
+    return process.env.OPENROUTER_API_KEY.trim();
+  }
+
+  if (typeof import.meta !== 'undefined' && import.meta.env?.VITE_OPENROUTER_API_KEY) {
+    return (import.meta.env.VITE_OPENROUTER_API_KEY as string).trim();
+  }
+
+  return '';
+}
+
+/**
+ * Checks if a valid OpenRouter API Key is configured.
+ */
+export function hasOpenRouterApiKey(): boolean {
+  return getOpenRouterApiKey().length > 0;
+}
+
+/**
+ * Returns the effective Google Gemini API Key.
+ * Precedence:
+ * 1. Explicit argument
+ * 2. UserSettings in LocalStorage (geminiApiKey)
+ * 3. Node process environment variable (GEMINI_API_KEY / API_KEY / VITE_GEMINI_API_KEY)
+ * 4. Vite environment variable (VITE_GEMINI_API_KEY)
+ */
+export function getGeminiApiKey(customKey?: string): string {
+  if (customKey !== undefined) {
+    return customKey.trim();
+  }
+
+  const stored = getStoredUserSettings();
+  if (stored.geminiApiKey && stored.geminiApiKey.trim().length > 0) {
+    return stored.geminiApiKey.trim();
+  }
+
+  if (typeof process !== 'undefined') {
+    if (process.env?.GEMINI_API_KEY !== undefined) return process.env.GEMINI_API_KEY.trim();
+    if (process.env?.API_KEY !== undefined) return process.env.API_KEY.trim();
+    if (process.env?.VITE_GEMINI_API_KEY !== undefined) return process.env.VITE_GEMINI_API_KEY.trim();
+  }
+
+  if (typeof import.meta !== 'undefined' && import.meta.env?.VITE_GEMINI_API_KEY) {
+    return (import.meta.env.VITE_GEMINI_API_KEY as string).trim();
+  }
+
+  return '';
+}
+
+/**
+ * Checks if a valid Google Gemini API Key is configured.
+ */
+export function hasGeminiApiKey(): boolean {
+  return getGeminiApiKey().length > 0;
+}