fix: update document.title on every page via useEffect

All pages are 'use client' so metadata exports don't work. Each page now
sets document.title via useEffect — static pages with a fixed string,
dynamic pages keyed on data so the title reflects the loaded content.

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

app/history/page.tsx

@@ -1,5 +1,6 @@
 'use client'
 import { useQuery, gql } from '@/lib/graphql/hooks'
+import { useEffect } from 'react'
 import Link from 'next/link'
 import { TeamFlag } from '@/components/team-flag'
 
@@ -23,6 +24,8 @@ interface Tournament {
 
 
 export default function HistoryPage() {
+  useEffect(() => { document.title = 'History · World Cup' }, [])
+
   const { data, loading } = useQuery(HISTORY_QUERY)
   const tournaments: Tournament[] = data?.tournaments ?? []
   const is2026InProgress = !tournaments.find(t => t.year === 2026)?.winner