feat(web): add quest API contracts

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

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

@@ -346,6 +346,7 @@ export type NpcMarker =
   | 'MERCHANT'
   | 'EXCHANGE'
   | 'QUEST_AVAILABLE'
+  | 'QUEST_IN_PROGRESS'
   | 'QUEST_TURN_IN';
 
 export interface NpcSummary {
@@ -468,3 +469,55 @@ export interface ShopPurchaseResult {
   silverSpent: number;
   silverBalance: number;
 }
+
+/**
+ * Quest transport types (Playable Slice 0.9).
+ *
+ * Mirrors the API's quest DTOs field for field. Nothing here is computed
+ * client-side: which step is current, how far along it is and whether it is
+ * blocked are all decided by the server (AGENTS.md §22).
+ */
+export type QuestStatus = 'AVAILABLE' | 'ACTIVE' | 'COMPLETED';
+export type QuestObjectiveType = 'COLLECT_ITEM' | 'TALK_TO_NPC';
+
+export interface QuestObjectiveView {
+  key: string;
+  description: string;
+  type: QuestObjectiveType;
+  targetKey: string;
+  required: number;
+  current: number;
+  completed: boolean;
+}
+
+export interface QuestView {
+  key: string;
+  title: string;
+  description: string;
+  status: QuestStatus;
+  objectives: QuestObjectiveView[];
+  currentObjectiveKey: string | null;
+  /** Why the current step cannot progress, when it cannot (slice §4, §12). */
+  hint: string | null;
+}
+
+export interface GrantedLootBag {
+  key: string;
+  name: string;
+  lootCategory: string;
+  capacity: number;
+}
+
+export interface QuestInteractionResult {
+  quest: QuestView;
+  /** What the NPC says for the step just performed (slice §5, §6, §8). */
+  npcLine: string | null;
+  /** Non-null only on the step that hands a bag over (slice §12 Bag UI). */
+  grantedBag: GrantedLootBag | null;
+  consumedItems: Array<{ itemKey: string; quantity: number }>;
+  rewards: {
+    factionKey: string | null;
+    reputation: number;
+    silver: number;
+  } | null;
+}

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

@@ -156,4 +156,47 @@ describe('GameApiService', () => {
     });
     req.flush({});
   });
+
+  it('reads the quest log', () => {
+    service.getQuests().subscribe();
+
+    const req = http.expectOne('/api/quests');
+    expect(req.request.method).toBe('GET');
+    req.flush([]);
+  });
+
+  it('accepts a quest without sending a body', () => {
+    service
+      .acceptQuest('south-gate-warden', 'trouble-beyond-the-gate')
+      .subscribe();
+
+    const req = http.expectOne(
+      '/api/npcs/south-gate-warden/quests/trouble-beyond-the-gate/accept',
+    );
+    expect(req.request.method).toBe('POST');
+    // The server decides where the quest starts; the client only names it.
+    expect(req.request.body).toEqual({});
+    req.flush({});
+  });
+
+  it('advances a quest step without naming the step', () => {
+    service
+      .advanceQuest('borin-quartermaster', 'trouble-beyond-the-gate')
+      .subscribe();
+
+    const req = http.expectOne(
+      '/api/npcs/borin-quartermaster/quests/trouble-beyond-the-gate/advance',
+    );
+    expect(req.request.method).toBe('POST');
+    expect(req.request.body).toEqual({});
+    req.flush({});
+  });
+
+  it('encodes npc and quest keys into the path', () => {
+    service.advanceQuest('odd/key', 'quest key').subscribe();
+
+    const req = http.expectOne('/api/npcs/odd%2Fkey/quests/quest%20key/advance');
+    expect(req.request.method).toBe('POST');
+    req.flush({});
+  });
 });

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

@@ -16,6 +16,8 @@ import {
   ExchangeView,
   NpcInteraction,
   NpcSummary,
+  QuestInteractionResult,
+  QuestView,
   ReputationEntry,
   ShopPurchaseResult,
   ShopView,
@@ -128,6 +130,40 @@ export class GameApiService {
     );
   }
 
+  getQuests(): Observable<QuestView[]> {
+    return this.http.get<QuestView[]>('/api/quests');
+  }
+
+  /**
+   * Takes a quest on. Only the two keys travel: the server decides whether this
+   * person offers it and where the quest starts (slice §10).
+   */
+  acceptQuest(
+    npcKey: string,
+    questKey: string,
+  ): Observable<QuestInteractionResult> {
+    return this.http.post<QuestInteractionResult>(
+      `/api/npcs/${encodeURIComponent(npcKey)}/quests/${encodeURIComponent(questKey)}/accept`,
+      {},
+    );
+  }
+
+  /**
+   * Performs whatever step this NPC is currently owed.
+   *
+   * The client never names the step. Which one is current, what it grants and
+   * what it consumes are the server's to decide (AGENTS.md §5).
+   */
+  advanceQuest(
+    npcKey: string,
+    questKey: string,
+  ): Observable<QuestInteractionResult> {
+    return this.http.post<QuestInteractionResult>(
+      `/api/npcs/${encodeURIComponent(npcKey)}/quests/${encodeURIComponent(questKey)}/advance`,
+      {},
+    );
+  }
+
   getShop(merchantKey: string): Observable<ShopView> {
     return this.http.get<ShopView>(
       `/api/merchants/${encodeURIComponent(merchantKey)}/shop`,