Persist auth session token in secure cookie storage

client/src/settings/settingsStore.ts

@@ -12,6 +12,9 @@ const MASTER_VOLUME_STORAGE_KEY = 'chatGridMasterVolume';
 const PEER_LISTEN_GAINS_STORAGE_KEY = 'chatGridPeerListenGains';
 const NICKNAME_STORAGE_KEY = 'spatialChatNickname';
 const AUTH_USERNAME_STORAGE_KEY = 'chatGridAuthUsername';
+const LEGACY_AUTH_SESSION_TOKEN_STORAGE_KEY = 'chatGridAuthSessionToken';
+const AUTH_SESSION_COOKIE_NAME = 'chgrid_session_token';
+const AUTH_SESSION_MAX_AGE_SECONDS = 14 * 24 * 60 * 60;
 
 type DevicePreference = {
   id: string;
@@ -27,6 +30,33 @@ type AudioDevicePreferences = {
  * Wraps localStorage reads/writes for client user settings.
  */
 export class SettingsStore {
+  private readCookie(name: string): string {
+    const cookie = document.cookie || '';
+    const parts = cookie.split(';');
+    for (const part of parts) {
+      const [rawKey, ...rest] = part.trim().split('=');
+      if (rawKey !== name) continue;
+      const rawValue = rest.join('=');
+      try {
+        return decodeURIComponent(rawValue);
+      } catch {
+        return rawValue;
+      }
+    }
+    return '';
+  }
+
+  private writeCookie(name: string, value: string, maxAgeSeconds: number): void {
+    const encoded = encodeURIComponent(value);
+    const secure = window.location.protocol === 'https:' ? '; Secure' : '';
+    document.cookie = `${name}=${encoded}; Path=/; Max-Age=${Math.max(0, Math.floor(maxAgeSeconds))}; SameSite=Lax${secure}`;
+  }
+
+  private clearCookie(name: string): void {
+    const secure = window.location.protocol === 'https:' ? '; Secure' : '';
+    document.cookie = `${name}=; Path=/; Max-Age=0; SameSite=Lax${secure}`;
+  }
+
   loadEffectLevels(): Partial<Record<'reverb' | 'echo' | 'flanger' | 'high_pass' | 'low_pass' | 'off', number>> | null {
     const raw = localStorage.getItem(EFFECT_LEVELS_STORAGE_KEY);
     if (!raw) return null;
@@ -115,17 +145,18 @@ export class SettingsStore {
   }
 
   loadAuthSessionToken(): string {
-    // Session tokens are intentionally not persisted in browser storage.
-    // Remove any legacy stored token and force fresh auth on reload.
-    localStorage.removeItem('chatGridAuthSessionToken');
-    return '';
+    // Session token is persisted in cookie storage (not localStorage).
+    localStorage.removeItem(LEGACY_AUTH_SESSION_TOKEN_STORAGE_KEY);
+    return this.readCookie(AUTH_SESSION_COOKIE_NAME);
   }
 
   saveAuthSessionToken(token: string): void {
-    // Session tokens are intentionally not persisted in browser storage.
-    // Keep behavior explicit: always clear any legacy token slot.
-    void token;
-    localStorage.removeItem('chatGridAuthSessionToken');
+    localStorage.removeItem(LEGACY_AUTH_SESSION_TOKEN_STORAGE_KEY);
+    if (token) {
+      this.writeCookie(AUTH_SESSION_COOKIE_NAME, token, AUTH_SESSION_MAX_AGE_SECONDS);
+      return;
+    }
+    this.clearCookie(AUTH_SESSION_COOKIE_NAME);
   }
 
   loadAuthUsername(): string {