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/players/[name]/page.tsx

@@ -1,6 +1,6 @@
 'use client'
 import { useQuery, gql } from '@/lib/graphql/hooks'
-import { use } from 'react'
+import { use, useEffect } from 'react'
 import Link from 'next/link'
 import { TeamFlag } from '@/components/team-flag'
 import { MatchCard } from '@/components/match-card'
@@ -32,6 +32,10 @@ export default function PlayerPage({ params }: { params: Promise<{ name: string
   const { data, loading } = useQuery(PLAYER_QUERY, { variables: { name } })
   const player: PlayerData | null = data?.player ?? null
 
+  useEffect(() => {
+    document.title = `${player?.playerName ?? name} · World Cup`
+  }, [player, name])
+
   // Fetch all goals for this player broken down by year
   const { data: goalsData } = useQuery(gql`
     query PlayerGoalsByYear($name: String!) {