security: migrate auth tokens to httpOnly cookies (hybrid bearer token approach)

Backend:
- CookieBearerToken middleware reads httpOnly cookie and injects Authorization
  header before Sanctum validates (prepended to API middleware group)
- SetAuthCookie trait provides cookie creation/expiry helpers with per-app
  cookie names (crewli_admin_token, crewli_app_token, crewli_portal_token)
- LoginController sets token via Set-Cookie, removes it from JSON body
- LogoutController expires the auth cookie on logout
- AuthRefreshController (POST /auth/refresh) rotates tokens with new cookie
- InvitationController accept also sets token via cookie, not JSON body
- All cookies: httpOnly, SameSite=Strict, Secure (in production)

Frontend (all three SPAs):
- Removed all localStorage token storage (apps/app, apps/portal)
- Removed all JS-readable cookie token storage (apps/admin)
- Removed Authorization: Bearer header interceptors from axios
- Auth stores now rely on GET /auth/me to validate httpOnly cookie
- Admin app: new Pinia auth store replaces useCookie-based auth pattern
- withCredentials: true ensures browser sends cookies automatically

Fixes security findings A13-1 (localStorage tokens) and A13-2 (admin
cookie flags). Tokens are now invisible to JavaScript.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/.env.example

@@ -30,7 +30,8 @@ SESSION_DRIVER=database
 SESSION_LIFETIME=120
 SESSION_ENCRYPT=false
 SESSION_PATH=/
-SESSION_DOMAIN=null
+# In production, use: SESSION_DOMAIN=.crewli.app
+SESSION_DOMAIN=localhost
 
 BROADCAST_CONNECTION=log
 FILESYSTEM_DISK=local