fix(api): count Cognito pool users directly

The runtime leaves EstimatedNumberOfUsers at 0, so the pool metadata now
carries a userCount from ListUsers (capped at 1000), which the delete
confirmation reads.

packages/api/src/adapter-aws/AwsUserPoolsAdapter.test.ts

@@ -121,12 +121,25 @@ describe('AwsUserPoolsAdapter', () => {
             signInWith: 'email',
             passwordPolicy: '8+ characters with uppercase, lowercase, number, symbol',
             estimatedNumberOfUsers: 1,
+            userCount: 0,
             mfaConfiguration: 'OFF',
             deletionProtection: 'INACTIVE',
             appClients: [{clientId: 'a8e5c7d38d3b4a1a97c9d822de', clientName: 'orders-users-client'}],
         })
     })
 
+    test('counts users itself, since the runtime leaves EstimatedNumberOfUsers at 0', async () => {
+        const {client} = stubCognito((command) => {
+            if (command instanceof DescribeUserPoolCommand) return {UserPool: {...pool, EstimatedNumberOfUsers: 0}}
+            if (command instanceof ListUsersCommand) return command.input.PaginationToken ? {Users: [alice]} : {Users: [alice, alice], PaginationToken: 'page-2'}
+            return {}
+        })
+        const resource = await new AwsUserPoolsAdapter(client).get(POOL_ID)
+
+        expect(resource?.metadata.userCount).toBe(3)
+        expect(resource?.metadata.estimatedNumberOfUsers).toBe(0)
+    })
+
     test('summarises a relaxed password policy without character rules', async () => {
         const {client} = stubCognito((command) => {
             if (command instanceof DescribeUserPoolCommand) return {UserPool: {...pool, Policies: {PasswordPolicy: {MinimumLength: 8, RequireUppercase: false, RequireLowercase: false, RequireNumbers: false, RequireSymbols: false}}}}