feat(combat): add frontend Combat models and API methods

Adds Combat domain models (Combat, CombatPlayer, CombatMonster, CombatEvent)
and three GameApiService methods to interact with backend combat endpoints:
- startCombat(encounterId): POST /api/hunt-encounters/:id/attack
- getCombat(combatId): GET /api/combats/:id
- performCombatAction(combatId, action): POST /api/combats/:id/actions

Includes test coverage for all three methods.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/web/src/app/core/api/game-api.models.ts

@@ -68,3 +68,41 @@ export interface HuntResult {
   location: LocationSummary;
   encounters: HuntEncounter[];
 }
+
+export type CombatStatus = 'ACTIVE' | 'WON' | 'LOST';
+export type CombatEventType = 'DAMAGE' | 'COMBAT_WON' | 'COMBAT_LOST';
+export type CombatSide = 'PLAYER' | 'MONSTER';
+export type CombatAction = 'ATTACK';
+
+export interface CombatEvent {
+  round: number;
+  sequence: number;
+  type: CombatEventType;
+  source: CombatSide;
+  target: CombatSide;
+  amount?: number;
+}
+
+export interface CombatPlayer {
+  name: string;
+  maxHp: number;
+  currentHp: number;
+}
+
+export interface CombatMonster {
+  key: string;
+  name: string;
+  level: number;
+  maxHp: number;
+  currentHp: number;
+  artworkPath: string;
+}
+
+export interface Combat {
+  id: string;
+  status: CombatStatus;
+  round: number;
+  player: CombatPlayer;
+  monster: CombatMonster;
+  events: CombatEvent[];
+}

apps/web/src/app/core/api/game-api.service.spec.ts

@@ -47,4 +47,30 @@ describe('GameApiService', () => {
     expect(request.request.body).toEqual({ targetLocationId: 'target-uuid' });
     request.flush({ status: 'IDLE' });
   });
+
+  it('posts to the encounter-scoped attack endpoint with an empty body to start a combat', () => {
+    service.startCombat('encounter-uuid').subscribe();
+
+    const request = http.expectOne('/api/hunt-encounters/encounter-uuid/attack');
+    expect(request.request.method).toBe('POST');
+    expect(request.request.body).toEqual({});
+    request.flush({});
+  });
+
+  it('gets a combat by id', () => {
+    service.getCombat('combat-uuid').subscribe();
+
+    const request = http.expectOne('/api/combats/combat-uuid');
+    expect(request.request.method).toBe('GET');
+    request.flush({});
+  });
+
+  it('posts only the action enum when performing a combat action', () => {
+    service.performCombatAction('combat-uuid', 'ATTACK').subscribe();
+
+    const request = http.expectOne('/api/combats/combat-uuid/actions');
+    expect(request.request.method).toBe('POST');
+    expect(request.request.body).toEqual({ action: 'ATTACK' });
+    request.flush({});
+  });
 });

apps/web/src/app/core/api/game-api.service.ts

@@ -1,7 +1,14 @@
 import { HttpClient } from '@angular/common/http';
 import { Injectable } from '@angular/core';
 import { Observable } from 'rxjs';
-import { CharacterResponse, CurrentLocationResponse, CurrentTravel, HuntResult } from './game-api.models';
+import {
+  CharacterResponse,
+  Combat,
+  CombatAction,
+  CurrentLocationResponse,
+  CurrentTravel,
+  HuntResult,
+} from './game-api.models';
 
 @Injectable({ providedIn: 'root' })
 export class GameApiService {
@@ -26,4 +33,16 @@ export class GameApiService {
   startHunt(): Observable<HuntResult> {
     return this.http.post<HuntResult>('/api/hunts', {});
   }
+
+  startCombat(encounterId: string): Observable<Combat> {
+    return this.http.post<Combat>(`/api/hunt-encounters/${encounterId}/attack`, {});
+  }
+
+  getCombat(combatId: string): Observable<Combat> {
+    return this.http.get<Combat>(`/api/combats/${combatId}`);
+  }
+
+  performCombatAction(combatId: string, action: CombatAction): Observable<Combat> {
+    return this.http.post<Combat>(`/api/combats/${combatId}/actions`, { action });
+  }
 }