DS1 follow-up: close the sb-token trust-bug class across all surfaces

The OAuth-only 'sb-token' localStorage key was read by profile, slip,
dashboard (recent-scans), settings, and tracker for their authenticated
fetches. Email/password users never had that key, so those fetches sent
no Authorization header and silently returned nothing.

- web/src/lib/authToken.js — currentAccessToken() reads the REAL Supabase
  session (sb-<ref>-auth-token, v2 top-level or v1 currentSession), legacy
  fallback. CommonJS so Jest can unit-test it (5 tests).
- Swept all 5 pages to the helper (scan already session-first from DS1).
- lib/api.ts (0 callers) + ParlayTray (unmounted) left as dead code.

236 suites / 2842 tests green, next build exit 0.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web/src/app/profile/page.tsx

@@ -3,6 +3,7 @@
 import { useEffect, useState } from 'react';
 import { useRouter } from 'next/navigation';
 import { useAuth } from '@/contexts/AuthContext';
+import { currentAccessToken } from '@/lib/authToken';
 
 interface FullProfile {
   id: string;
@@ -29,7 +30,7 @@ export default function ProfilePage() {
 
   useEffect(() => {
     if (!user) return;
-    const token = typeof window !== 'undefined' ? localStorage.getItem('sb-token') : null;
+    const token = currentAccessToken();
     fetch('/api/user/profile', {
       headers: token ? { Authorization: `Bearer ${token}` } : {},
     })
@@ -42,7 +43,7 @@ export default function ProfilePage() {
     if (!confirm('Cancel your subscription at the end of the current period?')) return;
     setWorking(true);
     setError('');
-    const token = typeof window !== 'undefined' ? localStorage.getItem('sb-token') : null;
+    const token = currentAccessToken();
     const res = await fetch('/api/user/profile', {
       method: 'PUT',
       headers: {