Add Google Workspace-only account for Claude (#163)

Adds a 'service-accounts' role that carries no GitHub, Discord, or
Google group config and exists solely to make its members eligible
for GWS user provisioning, plus a member entry that provisions
claude@modelcontextprotocol.io. Claude has no GitHub or Discord
handle, so none of the existing provisionUser roles fit.

src/config/users.ts

@@ -872,4 +872,11 @@ export const MEMBERS: readonly Member[] = [
     email: 'davideramian@anthropic.com',
     memberOf: [ROLE_IDS.ANTITRUST],
   },
+  {
+    email: 'claude@modelcontextprotocol.io',
+    firstName: 'Claude',
+    lastName: 'AI',
+    googleEmailPrefix: 'claude',
+    memberOf: [ROLE_IDS.SERVICE_ACCOUNTS],
+  },
 ] as const;