添加赛马实时进度播报

将比赛循环从race_engine移到commands中，每回合发送进度条：
  马匹名  |████████░░░░░░| 45.2m
race_engine改为提供tick/determine_champion/format_progress方法

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

danding_bot/plugins/group_horse_racing/race_engine.py

@@ -11,37 +11,23 @@ class RaceEngine:
         self.config = config
         self.active_tasks: dict[str, asyncio.Task] = {}
 
-    async def start_race(self, room: Room) -> asyncio.Task:
-        """Start race progression loop."""
-        task = asyncio.create_task(self._race_loop(room))
-        self.active_tasks[room.scope] = task
-        return task
+    def tick(self, room: Room):
+        """Advance race by one tick. Returns list of finished horses."""
+        room.tick_count += 1
 
-    async def _race_loop(self, room: Room):
-        """Main race progression loop."""
-        room.state = RoomState.RUNNING
+        for horse in room.horses.values():
+            if horse.state == HorseState.RACING:
+                distance = max(0, random.gauss(10, 3))
+                horse.position += distance
 
-        while room.state == RoomState.RUNNING:
-            await asyncio.sleep(self.config.RACE_TICK_INTERVAL)
-            room.tick_count += 1
+        finished_horses = [
+            h for h in room.horses.values()
+            if h.position >= self.config.RACE_DISTANCE
+        ]
 
-            for horse in room.horses.values():
-                if horse.state == HorseState.RACING:
-                    distance = max(0, random.gauss(10, 3))
-                    horse.position += distance
+        return finished_horses
 
-            finished_horses = [
-                h for h in room.horses.values()
-                if h.position >= self.config.RACE_DISTANCE
-            ]
-
-            if finished_horses:
-                champion = self._determine_champion(finished_horses)
-                room.champion_name = champion.name
-                room.state = RoomState.FINISHED
-                break
-
-    def _determine_champion(self, horses: list[Horse]) -> Horse:
+    def determine_champion(self, horses: list[Horse]) -> Horse:
         """Determine champion from tied horses."""
         if len(horses) == 1:
             return horses[0]
@@ -53,6 +39,10 @@ class RaceEngine:
 
         return horses[0]
 
+    def register_task(self, scope: str, task: asyncio.Task):
+        """Register an active race task."""
+        self.active_tasks[scope] = task
+
     def stop_race(self, scope: str):
         """Stop race and cancel task."""
         if scope in self.active_tasks:
@@ -60,3 +50,19 @@ class RaceEngine:
             if not task.done():
                 task.cancel()
             del self.active_tasks[scope]
+
+    def format_progress(self, room: Room) -> str:
+        """Format race progress as visual bar for each horse."""
+        distance = self.config.RACE_DISTANCE
+        bar_width = 20
+        lines = [f"【第{room.tick_count}回合】"]
+
+        # Sort by position descending for readability
+        sorted_horses = sorted(room.horses.values(), key=lambda h: h.position, reverse=True)
+        for horse in sorted_horses:
+            progress = min(horse.position / distance, 1.0)
+            filled = int(progress * bar_width)
+            bar = "█" * filled + "░" * (bar_width - filled)
+            lines.append(f"  {horse.name:<6} |{bar}| {horse.position:.1f}m")
+
+        return "\n".join(lines)