test(frontend): lock omitted reveal nickname contract

frontend/tests/angular-api-client.test.ts

@@ -1,7 +1,7 @@
 import { describe, expect, it, vi } from 'vitest';
 
 import { createAngularApiClient, type AngularHttpClientLike } from '../src/api/angular-client';
-import { mapSubmitGuessResponse } from '../src/api/mappers';
+import { mapSessionDetailResponse, mapSubmitGuessResponse } from '../src/api/mappers';
 
 describe('createAngularApiClient', () => {
   it('reads health and session detail using Django-compatible endpoints', async () => {
@@ -401,6 +401,68 @@ describe('createAngularApiClient', () => {
     expect(mapped.guess.fooled_player_id).toBeNull();
   });
 
+  it('keeps fooled_player_nickname omitted when canonical reveal payload omits fooled player refs', () => {
+    const mapped = mapSessionDetailResponse({
+      session: { code: 'ABCD12', status: 'reveal', host_id: 1, current_round: 1, players_count: 2 },
+      players: [
+        { id: 2, nickname: 'Maja', score: 10, is_connected: true },
+        { id: 3, nickname: 'Bo', score: 7, is_connected: true }
+      ],
+      round_question: {
+        id: 77,
+        round_number: 1,
+        prompt: 'Q?',
+        shown_at: '2026-03-01T18:00:00Z',
+        answers: [{ text: 'A' }, { text: 'B' }]
+      },
+      reveal: {
+        round_question_id: 77,
+        round_number: 1,
+        prompt: 'Q?',
+        correct_answer: 'A',
+        lies: [],
+        guesses: [
+          {
+            player_id: 3,
+            nickname: 'Bo',
+            selected_text: 'A',
+            is_correct: true,
+            created_at: '2026-03-01T18:00:15Z'
+          }
+        ]
+      },
+      phase_view_model: {
+        status: 'reveal',
+        round_number: 1,
+        players_count: 2,
+        constraints: {
+          min_players_to_start: 2,
+          max_players_mvp: 8,
+          min_players_reached: true,
+          max_players_allowed: true
+        },
+        host: {
+          can_start_round: false,
+          can_show_question: false,
+          can_mix_answers: false,
+          can_calculate_scores: false,
+          can_reveal_scoreboard: true,
+          can_start_next_round: false,
+          can_finish_game: false
+        },
+        player: {
+          can_join: true,
+          can_submit_lie: false,
+          can_submit_guess: false,
+          can_view_final_result: false
+        }
+      }
+    });
+
+    expect(mapped.reveal?.guesses[0].fooled_player_id).toBeNull();
+    expect(mapped.reveal?.guesses[0]).not.toHaveProperty('fooled_player_nickname');
+  });
+
   it('maps host/player gameplay endpoints through typed response mappers', async () => {
     const get = vi.fn<AngularHttpClientLike['get']>(async <T>(url: string) => {
       if (url === '/lobby/sessions/ABCD12/scoreboard') {