[Bug] Writer tab: useState(checkExpired) causes SSR hydration mismatch

[realproject7]

Problem

PR #834 uses useState(checkExpired) as a lazy initializer, which calls Date.now() during the initial render. Server and client timestamps differ, causing a potential React hydration mismatch warning for storylines near the expiry boundary.

Also: the 1-second setInterval polling is wasteful for a badge that only transitions once (active → expired). A setTimeout targeting the exact expiry time would be more efficient.

Solution

1. Change useState(checkExpired) to useState(false) — let the existing useEffect set the correct value on mount
2. Replace setInterval(1000) with setTimeout calculated from expiryTime - Date.now()

Acceptance Criteria

• No SSR hydration mismatch warnings
• Badge still correctly shows expired/active/complete
• No 1-second polling — use targeted setTimeout instead
• Cleanup timeout on unmount

Branch

task/<issue>-badge-hydration-fix