fix: suppress Apollo cache warnings for Match.team1 / Match.team2

Different queries fetch Team with different field sets (some include slug,
others don't). merge: true tells InMemoryCache to combine fields rather
than replace, avoiding the "cache data may be lost" warning.

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

lib/graphql/client.ts

@@ -10,6 +10,7 @@ function createClient() {
     cache: new InMemoryCache({
       typePolicies: {
         Team: { fields: { stats: { merge: true } } },
+        Match: { fields: { team1: { merge: true }, team2: { merge: true } } },
       },
     }),
     defaultOptions: { watchQuery: { fetchPolicy: 'cache-and-network' } },