feat(#28): add break rule & order to games and UI

- Types: add BreakRule, break metadata to StandardGame, extend NewGameData/steps
- NewGame: add BreakRule and BreakOrder steps with auto-advance
- NewGameScreen: wire new steps into flow
- GameService: set up defaults, persist break order, compute next breaker on +1
- GameDetail: show breaker indicator; treat -1 as undo equivalent

Backfill defaults for existing games via service logic.

Refs #28

src/services/gameService.ts

@@ -1,4 +1,4 @@
-import type { Game, GameType, StandardGame, EndlosGame, NewGameData } from '../types/game';
+import type { Game, GameType, StandardGame, EndlosGame, NewGameData, BreakRule } from '../types/game';
 import { IndexedDBService } from './indexedDBService';
 
 const LOCAL_STORAGE_KEY = 'bscscore_games';
@@ -163,6 +163,25 @@ export class GameService {
       player2: gameData.player2,
       score1: 0,
       score2: 0,
+      breakRule: (gameData.breakRule as BreakRule) || 'winnerbreak',
+      breakOrder: (() => {
+        // Determine break order from inputs, fallback defaults
+        const players: number[] = [1, 2];
+        if (gameData.player3?.trim()) players.push(3);
+        const first = (typeof gameData.breakFirst === 'number' ? gameData.breakFirst : 1) as number;
+        const second = (typeof gameData.breakSecond === 'number' ? gameData.breakSecond : (players.includes(2) && first !== 2 ? 2 : (players.includes(3) ? 3 : 2))) as number;
+        const order = [first];
+        if (players.length === 2) {
+          order.push(first === 1 ? 2 : 1);
+        } else {
+          // 3 players: add chosen second, then the remaining third
+          order.push(second);
+          const third = [1,2,3].find(p => p !== first && p !== second)!;
+          order.push(third);
+        }
+        return order;
+      })(),
+      currentBreakerIdx: 0,
     };
 
     if (gameData.player3) {
@@ -185,6 +204,23 @@ export class GameService {
       updated.score3 = Math.max(0, updated.score3 + change);
     }
     
+    // Breaker logic
+    if (change > 0) {
+      if ((updated.breakRule || 'winnerbreak') === 'winnerbreak') {
+        // Winner keeps break: set breaker to this player
+        const order = updated.breakOrder || [1,2].concat(updated.score3 !== undefined ? [3] : []);
+        updated.breakOrder = order;
+        const idx = order.findIndex(p => p === player);
+        updated.currentBreakerIdx = idx >= 0 ? idx : 0;
+      } else {
+        // Wechselbreak: rotate to next
+        const order = updated.breakOrder || [1,2].concat(updated.score3 !== undefined ? [3] : []);
+        updated.breakOrder = order;
+        const curr = typeof updated.currentBreakerIdx === 'number' ? updated.currentBreakerIdx : 0;
+        updated.currentBreakerIdx = (curr + 1) % order.length;
+      }
+    }
+
     updated.updatedAt = new Date().toISOString();
     return updated;
   }