feat(combat): validate potions, persist telegraph state, and expose both on the combat DTO

Also updates the pre-existing exact-equality playerState assertion in
combat-equipment-integration.spec.ts, which broke from the new
potionsRemaining field but wasn't listed in the task brief's file scope.

apps/api/src/combat/combat.service.ts

@@ -13,12 +13,13 @@ import { TravelService } from '../travel/travel.service';
 import { TravelStatus } from '../travel/travel-status.enum';
 import { CombatAction } from './combat-action.enum';
 import { CombatEngineService } from './combat-engine.service';
-import { CombatEngineState } from './combat-engine.types';
+import { CombatEngineState, CombatIntent } from './combat-engine.types';
 import {
   characterNotFound,
   characterTravelling,
   combatAlreadyActive,
   combatAlreadyFinished,
+  combatNoPotionsRemaining,
   combatNotFound,
   combatStateInvalid,
   huntEncounterAlreadyConsumed,
@@ -27,12 +28,18 @@ import {
 } from './combat.errors';
 import { CombatStatus } from './combat-status.enum';
 import { CombatEvent } from './entities/combat-event.entity';
-import { Combat } from './entities/combat.entity';
+import { Combat, CombatPlayerState } from './entities/combat.entity';
+
+// Playable Slice 0.6 spec §3: fixed at 2 for V1, not yet backed by the
+// persistent consumable inventory.
+const STARTING_POTION_COUNT = 2;
 
 export interface CombatPlayerDto {
   name: string;
   maxHp: number;
   currentHp: number;
+  potionsRemaining: number;
+  potionsMax: number;
 }
 
 export interface CombatMonsterDto {
@@ -42,6 +49,7 @@ export interface CombatMonsterDto {
   maxHp: number;
   currentHp: number;
   artworkPath: string;
+  pendingIntent: CombatIntent | null;
 }
 
 export interface CombatEventDto {
@@ -142,6 +150,7 @@ export class CombatService {
           attack: playerStats.attack,
           weaponDamage: playerStats.weaponDamage,
           armor: playerStats.armor,
+          potionsRemaining: STARTING_POTION_COUNT,
         },
         monsterState: { attack: monster.attack, armor: monster.armor },
         completedAt: null,
@@ -220,6 +229,9 @@ export class CombatService {
       if (combat.status !== CombatStatus.ACTIVE) {
         throw combatAlreadyFinished();
       }
+      if (action === CombatAction.POTION && (combat.playerState.potionsRemaining ?? 0) <= 0) {
+        throw combatNoPotionsRemaining();
+      }
 
       const actionRound = combat.round;
       const engineState = this.toEngineState(combat);
@@ -229,6 +241,8 @@ export class CombatService {
       combat.status = result.state.status;
       combat.playerCurrentHp = result.state.player.currentHp;
       combat.monsterCurrentHp = result.state.monster.currentHp;
+      combat.playerState = result.state.player.stats as CombatPlayerState;
+      combat.monsterState = result.state.monster.stats;
       if (combat.status !== CombatStatus.ACTIVE) {
         combat.completedAt = new Date();
         await this.settleEncounter(
@@ -386,6 +400,8 @@ export class CombatService {
         name: playerName,
         maxHp: combat.playerMaxHp,
         currentHp: combat.playerCurrentHp,
+        potionsRemaining: combat.playerState.potionsRemaining,
+        potionsMax: STARTING_POTION_COUNT,
       },
       monster: {
         key: monster.key,
@@ -394,6 +410,7 @@ export class CombatService {
         maxHp: combat.monsterMaxHp,
         currentHp: combat.monsterCurrentHp,
         artworkPath: monster.artworkPath,
+        pendingIntent: combat.monsterState.pendingAction ?? null,
       },
       events: events.map((event) => ({
         round: event.round,