feat(replay): M9-6 Bar Replay 线性重放（as_of 逐日仅用当时数据）

- domain/entities/replay.py：ReplayDay{top/events/counts}/ReplayResult 时间线
- ReplayService：universe.symbols 白名单必填（≤40）且重放交易日 ≤90（防全市场长任务）；
  每个交易日以 <=as_of 数据经同一 signal/score 引擎生成帧
- POST /api/replays（边界校验）→ 时间线；供前端 Bar Replay 控件（v3 §20.6 阶段二）
- tests/test_replays.py：重放帧 == 回测 selection_history 逐调仓日一致；范围约束；
  后段暴涨股不泄漏进早段帧（未来函数）；API 400/200；全量 pytest 通过

backend/app/api/deps.py

@@ -11,6 +11,7 @@ from fastapi import Depends
 from sqlalchemy.orm import Session
 
 from app.application.services.chart_service import ChartService
+from app.application.services.replay_service import ReplayService
 from app.application.services.selection_service import SelectionService
 from app.application.services.signal_service import SignalService
 from app.domain.repositories.composite import CompositeRepository
@@ -89,6 +90,13 @@ def _service_factory(
     return ResearchService(stock_repo, daily_repo, engine)
 
 
+def _replay_service_factory(
+    stock_repo: Annotated[StockRepository, Depends(_stock_repo_factory)],
+    daily_repo: Annotated[DailyBarRepository, Depends(_daily_repo_factory)],
+) -> ReplayService:
+    return ReplayService(stock_repo, daily_repo)
+
+
 def _signal_service_factory(
     stock_repo: Annotated[StockRepository, Depends(_stock_repo_factory)],
     daily_repo: Annotated[DailyBarRepository, Depends(_daily_repo_factory)],
@@ -135,6 +143,7 @@ FactorRepoDep = Annotated[FactorRepository, Depends(_factor_repo_factory)]
 CompositeRepoDep = Annotated[CompositeRepository, Depends(_composite_repo_factory)]
 SignalRepoDep = Annotated[SignalRepository, Depends(_signal_repo_factory)]
 SignalServiceDep = Annotated[SignalService, Depends(_signal_service_factory)]
+ReplayServiceDep = Annotated[ReplayService, Depends(_replay_service_factory)]
 ChartServiceDep = Annotated[ChartService, Depends(_chart_service_factory)]
 StrategyRepoDep = Annotated[StrategyRepository, Depends(_strategy_repo_factory)]
 

backend/app/api/replays.py

@@ -0,0 +1,33 @@
+"""Bar Replay API（M9-6）：POST /api/replays —— 线性重放选股/信号时间线。"""
+
+from __future__ import annotations
+
+from datetime import date
+
+from fastapi import APIRouter, HTTPException
+from pydantic import BaseModel, Field
+
+from app.api.deps import ReplayServiceDep
+from app.domain.entities.replay import ReplayResult
+from app.domain.entities.selection import SelectionQuery
+from app.domain.entities.signal import SignalRules
+
+router = APIRouter(prefix="/replays", tags=["replays"])
+
+
+class ReplayRequest(BaseModel):
+    query: SelectionQuery
+    rules: SignalRules = SignalRules()
+    start: date
+    end: date
+    top_n: int = Field(default=5, ge=1, le=20)
+
+
+@router.post("", response_model=ReplayResult, summary="线性重放（as_of 逐日，仅用当时数据）")
+def run_replay(req: ReplayRequest, service: ReplayServiceDep) -> ReplayResult:
+    if req.start >= req.end:
+        raise HTTPException(status_code=400, detail="start 必须早于 end")
+    try:
+        return service.replay(req.query, req.rules, req.start, req.end, req.top_n)
+    except ValueError as exc:
+        raise HTTPException(status_code=400, detail=str(exc)) from exc

backend/app/api/router.py

@@ -16,6 +16,7 @@ from app.api import (
     factors,
     health,
     jobs,
+    replays,
     research,
     selections,
     signals,
@@ -31,6 +32,7 @@ api_router.include_router(composites.router)
 api_router.include_router(research.router)
 api_router.include_router(selections.router)
 api_router.include_router(charts.router)
+api_router.include_router(replays.router)
 api_router.include_router(signals.router)
 api_router.include_router(strategies.router)
 api_router.include_router(jobs.router)

backend/app/application/services/replay_service.py

@@ -0,0 +1,85 @@
+"""Bar Replay 服务（M9-6）：线性逐交易日重放选股+信号（as_of 语义）。
+
+- 范围约束：universe.symbols 必填（≤ 40 只）、重放交易日 ≤ 90 —— 避免全市场长任务
+- 每日计算只使用 <= as_of 数据（与 select/signal/回测同一引擎与口径）
+- ReplayDay.events 按 rank 升序；top 取前 N（意图排名，与回测 selection_history 对齐）
+"""
+
+from __future__ import annotations
+
+from datetime import date, timedelta
+
+import pandas as pd
+
+from app.domain.entities.replay import ReplayDay, ReplayResult, ReplayTop
+from app.domain.entities.selection import SelectionQuery
+from app.domain.entities.signal import SignalRules
+from app.domain.repositories.market import DailyBarRepository, StockRepository
+from app.quant.selection import factor_columns
+from app.quant.service import filter_stocks, load_daily_df
+from app.quant.signal import generate_signals
+
+MAX_SYMBOLS = 40
+MAX_DAYS = 90
+
+
+class ReplayService:
+    def __init__(self, stock_repo: StockRepository, daily_repo: DailyBarRepository) -> None:
+        self._stock_repo = stock_repo
+        self._daily_repo = daily_repo
+
+    def replay(
+        self,
+        query: SelectionQuery,
+        rules: SignalRules,
+        start: date,
+        end: date,
+        top_n: int = 5,
+    ) -> ReplayResult:
+        symbols = list(query.universe.symbols or [])
+        if not symbols:
+            raise ValueError("Bar Replay 需要 universe.symbols 白名单（≤40 只），避免全市场长任务")
+        if len(symbols) > MAX_SYMBOLS:
+            raise ValueError(f"Bar Replay 白名单最多 {MAX_SYMBOLS} 只，当前 {len(symbols)}")
+        stocks = filter_stocks(self._stock_repo.list(), query.universe, as_of=start)
+        if not stocks:
+            return ReplayResult(start=start, end=end, top_n=top_n)
+
+        columns = sorted(factor_columns(query))
+        daily = load_daily_df(
+            self._daily_repo,
+            symbols,
+            start - timedelta(days=query.warmup_days),
+            end,
+            columns,
+            adjust=query.price_adjustment,
+        )
+        if daily.empty:
+            return ReplayResult(start=start, end=end, top_n=top_n)
+        trading_days = sorted(
+            pd.to_datetime(daily["trade_date"].unique())
+        )
+        days = [d for d in trading_days if start <= d.date() <= end]
+        if len(days) > MAX_DAYS:
+            raise ValueError(f"重放区间交易日 {len(days)} > 上限 {MAX_DAYS}，请缩短区间")
+
+        out_days: list[ReplayDay] = []
+        for d in days:
+            res = generate_signals(daily, query, rules, as_of=d.date())
+            top = [
+                ReplayTop(symbol=e.symbol, score=e.score or 0.0)
+                for e in res.events[:top_n]
+            ]
+            out_days.append(
+                ReplayDay(
+                    as_of=d.date(),
+                    top=top,
+                    events=res.events,
+                    counts={
+                        "buy": res.statistics.buy,
+                        "watch": res.statistics.watch,
+                        "sell": res.statistics.sell,
+                    },
+                )
+            )
+        return ReplayResult(start=start, end=end, days=out_days, top_n=top_n)

backend/app/domain/entities/replay.py

@@ -0,0 +1,34 @@
+"""Bar Replay（v3 §20.6，第二阶段 MVP）领域实体。
+
+线性重放：对给定选股查询与信号规则，在交易日序列上逐日以「当日为止的数据」执行
+（as_of 语义），输出每日时间线（意图 Top + 信号 + 计数），用于核对：
+- 未来函数：每日计算只用 <= as_of 数据（与静态研究同一引擎）
+- 一致性：重放某日结果 == 该日独立 select/signal 结果（亦 == 回测该调仓日意图）
+"""
+
+from __future__ import annotations
+
+from datetime import date
+
+from pydantic import BaseModel, Field
+
+from app.domain.entities.signal import SignalEvent
+
+
+class ReplayTop(BaseModel):
+    symbol: str
+    score: float
+
+
+class ReplayDay(BaseModel):
+    as_of: date
+    top: list[ReplayTop] = Field(default_factory=list, description="意图排名前 N（score 降序）")
+    events: list[SignalEvent] = Field(default_factory=list, description="当日信号（<=max_output_rank）")
+    counts: dict[str, int] = Field(default_factory=dict, description="BUY/WATCH/SELL 计数")
+
+
+class ReplayResult(BaseModel):
+    start: date
+    end: date
+    days: list[ReplayDay] = Field(default_factory=list)
+    top_n: int = 5