fix(pitch-deck): align JWT expiry with session lifetime (24h)

JWT was set to 1h while the session cookie lived 24h. After 1 hour the
cookie persisted but jwtVerify failed, making /api/auth/me return 401
and the re-click redirect fall through to the already-used token error.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pitch-deck/lib/auth.ts

@@ -4,8 +4,8 @@ import { cookies } from 'next/headers'
 import pool from './db'
 
 const COOKIE_NAME = 'pitch_session'
-const JWT_EXPIRY = '1h'
 const SESSION_EXPIRY_HOURS = 24
+const JWT_EXPIRY = `${SESSION_EXPIRY_HOURS}h`
 
 function getJwtSecret() {
   const secret = process.env.PITCH_JWT_SECRET