fix: override stale DB iso2 with registry for known defunct nations

The DB still holds old codes (su, yu) from before the null mapping was
added. TeamFlag now checks TEAM_ISO by name first so the registry wins
over any stale value the DB returns.

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

components/team-flag.tsx

@@ -1,4 +1,4 @@
-import { getIso } from '@/lib/iso-codes'
+import { TEAM_ISO, getIso } from '@/lib/iso-codes'
 
 interface Props {
   name: string
@@ -17,7 +17,9 @@ const placeholderSize = {
 }
 
 export function TeamFlag({ name, iso2, size = 'md', className = '' }: Props) {
-  const code = iso2 !== undefined ? iso2 : getIso(name)
+  // If the name is in our registry, trust it over the DB value (which may be stale).
+  // For unknown teams, fall back to the DB iso2.
+  const code = name in TEAM_ISO ? TEAM_ISO[name] : (iso2 ?? getIso(name))
 
   if (!code) {
     const abbr = name