feat: ambassador stats endpoint (#1611)

packages/espressocash_api/lib/espressocash_api.dart

@@ -2,6 +2,7 @@ export 'package:jupiter_aggregator/jupiter_aggregator.dart';
 
 export 'src/client.dart';
 export 'src/dto/ambassador_referral.dart';
+export 'src/dto/ambassador_stats.dart';
 export 'src/dto/create_payment.dart';
 export 'src/dto/dln_payment.dart';
 export 'src/dto/durable_transactions.dart';

packages/espressocash_api/lib/src/client.dart

@@ -181,6 +181,9 @@ abstract class EspressoCashClient {
   Future<void> addAmbassadorReferral(
     @Body() AmbassadorReferralRequestDto request,
   );
+
+  @POST('/ambassador/stats')
+  Future<AmbassadorStatsResponseDto> getAmbassadorStats();
 }
 
 extension EspressoCashClientExt on EspressoCashClient {

packages/espressocash_api/lib/src/dto/ambassador_stats.dart

@@ -0,0 +1,14 @@
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+part 'ambassador_stats.freezed.dart';
+part 'ambassador_stats.g.dart';
+
+@freezed
+class AmbassadorStatsResponseDto with _$AmbassadorStatsResponseDto {
+  const factory AmbassadorStatsResponseDto({
+    required int referralCount,
+  }) = _AmbassadorStatsResponseDto;
+
+  factory AmbassadorStatsResponseDto.fromJson(Map<String, dynamic> json) =>
+      _$AmbassadorStatsResponseDtoFromJson(json);
+}