全量修复:预测系统正确性、安全性与部署问题

P0 严重问题修复:
- 修复 form_slice/stats_slice 主客身份反转(历史比赛视角错误)
- 修复 understat.py httpx 未导入导致的 NameError
- 修复 LLM 解析失败时静默产生假成功预测(0-0 平局+置信度0.5)

预测路径修复:
- multi-agent 路径增加 backtest cutoff 透传,回测防泄漏生效
- H2H 切片汇总统计改为从当前主队视角计数
- 预测唯一约束增加 mode+run_type 维度,防止回测覆盖实盘预测

伤停管线修复:
- IntegrityError 后不再整批回滚丢数据(改用逐条 flush)
- return_date 正确解析并写入
- retrieved_at 比较统一用 date() 避免当天数据不可见
- 唯一索引改为 partial unique index(排除 NULL 重复)
- HTTP 缓存 TTL 从 7 天改为 6 小时

安全与连接管理:
- /api/v1/predict 增加内存滑动窗口限流(10次/分钟/IP)
- 预测路由改用短 session 模式,LLM 调用期间不持有 DB 连接

Docker 部署修复:
- 修复 .dockerignore 排除 *.md 导致 COPY README.md 失败
- 容器内 DATABASE_URL 使用 postgres 服务名(非 localhost)
- 启动时自动执行 alembic upgrade head
- 前端改用多阶段构建(Dockerfile.frontend)

新增测试(5个文件,24+用例):
- test_p0_home_away.py: 主客身份反转回归测试
- test_p0_parse_failure.py: LLM 解析失败回归测试
- test_multi_agent_cutoff.py: multi-agent cutoff 透传测试
- test_h2h_perspective.py: H2H 视角测试
- test_injuries_pipeline.py: 伤停管线 5 项修复测试
- test_predict_protection.py: 限流+短 session 测试
- test_prediction_unique_constraint.py: 唯一约束测试

迁移:
- 0012_injuries_partial_unique_and_return_date.py
- 0013_predictions_unique_constraint_mode_run_type.py

src/llm/context_builder.py

@@ -71,6 +71,7 @@ class MatchContext:
     has_stats: bool
     has_injuries: bool
     match_dt: object | None = None  # 比赛时间(回测防泄漏 + 快照用)
+    cutoff: object | None = None  # 实际使用的数据截止时间(用于落库记录)
 
 
 @dataclass
@@ -144,20 +145,38 @@ async def h2h_slice(header: MatchHeader, *, limit: int = 8, before=None, db: Asy
     lines = [f"── 历史交锋(近 {limit} 次) ──"]
     n_with_score = 0
     if h2h:
-        home_wins = draws = away_wins = 0
+        # 从当前主队视角统计:判断当前主队在每场交锋中是主是客
+        current_home_wins = current_home_draws = current_home_losses = 0
         for hm in h2h:
             d = hm.match_date.strftime("%Y-%m") if hm.match_date else "?"
             if hm.home_goals is not None:
                 n_with_score += 1
-                if hm.home_goals > hm.away_goals: home_wins += 1
-                elif hm.home_goals == hm.away_goals: draws += 1
-                else: away_wins += 1
+                # 判断当前主队当时是主队还是客队
+                if hm.home_team_id == header.home_team_id:
+                    # 当前主队当时是主队
+                    if hm.home_goals > hm.away_goals:
+                        current_home_wins += 1
+                    elif hm.home_goals == hm.away_goals:
+                        current_home_draws += 1
+                    else:
+                        current_home_losses += 1
+                else:
+                    # 当前主队当时是客队(从客队视角看赛果)
+                    if hm.away_goals > hm.home_goals:
+                        current_home_wins += 1
+                    elif hm.away_goals == hm.home_goals:
+                        current_home_draws += 1
+                    else:
+                        current_home_losses += 1
                 lines.append(f"  {d}: {hm.home_team.name} {hm.home_goals}-{hm.away_goals} {hm.away_team.name}")
             else:
                 lines.append(f"  {d}: {hm.home_team.name} vs {hm.away_team.name} (无比分)")
-        total = home_wins + draws + away_wins
+        total = current_home_wins + current_home_draws + current_home_losses
         if total:
-            lines.append(f"  总计 {total} 场: 主队 {home_wins}胜 {draws}平 {away_wins}负")
+            lines.append(
+                f"  总计 {total} 场(从当前主队 {header.home_name} 视角): "
+                f"{current_home_wins}胜 {current_home_draws}平 {current_home_losses}负"
+            )
     else:
         lines.append("  无数据")
     # has_data 以「有比分的交锋」为准:仅有对阵无比分时不足以支撑分析
@@ -178,14 +197,18 @@ async def form_slice(header: MatchHeader, *, limit: int = 5, before=None, db: As
             away_form = await _get_form(new_db, header.away_team_id, before=before, limit=limit)
     lines = []
     n_scored = 0
-    for label, name, form, side in (
-        ("主队", header.home_name, home_form, "home"),
-        ("客队", header.away_name, away_form, "away"),
+    # P0-1 修复:每场历史比赛必须根据「该队当时是主是客」判断 side,
+    # 不能用本场 side 硬套 —— 否则客场输球会被算成主场赢球。
+    for label, name, form, team_id in (
+        ("主队", header.home_name, home_form, header.home_team_id),
+        ("客队", header.away_name, away_form, header.away_team_id),
     ):
         lines.append(f"── {label}近况({name},近 {limit} 场) ──")
         if form:
             wins = draws = losses = 0
             for fm in form:
+                is_home = (fm.home_team_id == team_id)
+                side = "home" if is_home else "away"
                 o = _outcome(fm.home_goals, fm.away_goals, side)
                 if o == "W": wins += 1
                 elif o == "D": draws += 1
@@ -195,9 +218,9 @@ async def form_slice(header: MatchHeader, *, limit: int = 5, before=None, db: As
                 score = f"{fm.home_goals}-{fm.away_goals}" if fm.home_goals is not None else "vs"
                 xg = ""
                 if fm.stats and _is_stats_available(fm.stats, before) and fm.stats.home_xg is not None:
-                    own = fm.stats.home_xg if side == "home" else fm.stats.away_xg
+                    own = fm.stats.home_xg if is_home else fm.stats.away_xg
                     xg = f" (xG {own:.1f})"
-                opp = fm.away_team.name if side == "home" else fm.home_team.name
+                opp = fm.away_team.name if is_home else fm.home_team.name
                 lines.append(f"  {o} {score} vs {opp}{xg}")
             lines.append(f"  近 {len(form)} 场: {wins}胜 {draws}平 {losses}负")
         else:
@@ -219,30 +242,33 @@ async def stats_slice(header: MatchHeader, *, limit: int = 10, before=None, db:
             away_form = await _get_form(new_db, header.away_team_id, before=before, limit=limit)
     lines = [f"── 攻防数据(近 {limit} 场) ──"]
     n_total = 0
-    for label, name, form, side in (
-        ("主队", header.home_name, home_form, "home"),
-        ("客队", header.away_name, away_form, "away"),
+    # P0-1 修复:每场历史比赛必须根据「该队当时是主是客」判断 side,
+    # 不能用本场 side 硬套 —— 否则进球/失球/xG 全部算反。
+    for label, name, form, team_id in (
+        ("主队", header.home_name, home_form, header.home_team_id),
+        ("客队", header.away_name, away_form, header.away_team_id),
     ):
         if form:
             gf = ga = shots = sot = poss = xg = xga = 0
             n = n_shots = n_poss = n_xg = 0
             for fm in form:
                 if fm.home_goals is None: continue
-                gf += fm.home_goals if side == "home" else fm.away_goals
-                ga += fm.away_goals if side == "home" else fm.home_goals
+                is_home = (fm.home_team_id == team_id)
+                gf += fm.home_goals if is_home else fm.away_goals
+                ga += fm.away_goals if is_home else fm.home_goals
                 n += 1
                 # 只使用 cutoff 之前已可用的统计数据
                 if fm.stats and _is_stats_available(fm.stats, before):
                     if fm.stats.home_shots is not None:
-                        shots += fm.stats.home_shots if side == "home" else fm.stats.away_shots
-                        sot += fm.stats.home_shots_on_target if side == "home" else fm.stats.away_shots_on_target
+                        shots += fm.stats.home_shots if is_home else fm.stats.away_shots
+                        sot += fm.stats.home_shots_on_target if is_home else fm.stats.away_shots_on_target
                         n_shots += 1
                     if fm.stats.home_possession is not None:
-                        poss += fm.stats.home_possession if side == "home" else (100 - fm.stats.home_possession)
+                        poss += fm.stats.home_possession if is_home else (100 - fm.stats.home_possession)
                         n_poss += 1
                     if fm.stats.home_xg is not None:
-                        xg += fm.stats.home_xg if side == "home" else fm.stats.away_xg
-                        xga += fm.stats.away_xg if side == "home" else fm.stats.home_xg
+                        xg += fm.stats.home_xg if is_home else fm.stats.away_xg
+                        xga += fm.stats.away_xg if is_home else fm.stats.home_xg
                         n_xg += 1
             n_total += n
             if n > 0:
@@ -340,23 +366,27 @@ async def injuries_slice(header: MatchHeader, *, before=None, db: AsyncSession |
 # 单 agent 路径: 拼接全部切片(行为与旧版一致)
 # ============================================================
 
-async def build_context(match_id: int, *, form_last: int = 5, h2h_last: int = 5, backtest: bool = False) -> MatchContext:
-    """单 agent 路径的完整上下文: 拼接全部切片(before=比赛时间,防未来信息)。
+async def build_context(match_id: int, *, form_last: int = 5, h2h_last: int = 5, backtest: bool = False, cutoff_at=None) -> MatchContext:
+    """单 agent 路径的完整上下文: 拼接全部切片(before=cutoff,防未来信息)。
 
     has_stats / has_injuries 直接取切片显式声明的 has_data,
     不再靠文案子串匹配(见审查报告 P2-1)。
 
     P2-6: backtest=True 时 cutoff = match_date - 1天,确保只用赛前数据。
+    cutoff_at: 显式截止时间(优先于 backtest 自动计算)。
 
     P1-1: 使用单个共享 session 贯穿所有切片查询,避免连接池耗尽。
     """
     async with AsyncSessionLocal() as db:
         header = await load_match_header(match_id, db=db)
-        # P2-6: 回测模式下 cutoff 提前 1 天,防止比赛日数据泄漏
-        cutoff = header.match_dt
-        if backtest and header.match_dt:
+        # 计算数据截止时间: 显式 > backtest 自动计算 > 默认(比赛时间)
+        if cutoff_at is not None:
+            cutoff = cutoff_at
+        elif backtest and header.match_dt:
             from datetime import timedelta
             cutoff = header.match_dt - timedelta(days=1)
+        else:
+            cutoff = header.match_dt
         parts = [header_text(header), ""]
 
         form_res = await form_slice(header, limit=form_last, before=cutoff, db=db)
@@ -384,6 +414,7 @@ async def build_context(match_id: int, *, form_last: int = 5, h2h_last: int = 5,
             has_stats=form_res.has_data or stats_res.has_data,
             has_injuries=injuries_res.has_data,
             match_dt=header.match_dt,
+            cutoff=cutoff,
         )