feat(web): add reward models and the reusable item card

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

apps/web/src/app/features/combat/combat-page/combat-page.component.spec.ts

@@ -23,6 +23,7 @@ const activeCombat: Combat = {
     { round: 1, sequence: 1, type: 'DAMAGE', source: 'PLAYER', target: 'MONSTER', amount: 14 },
     { round: 1, sequence: 2, type: 'DAMAGE', source: 'MONSTER', target: 'PLAYER', amount: 5 },
   ],
+  rewards: null,
 };
 
 const monsterHitLine = 'Aschenratte trifft Aric Duskwalker für 5 Schaden.';