feat(admin): Phase 7 计费审计+4层额度策略 — 流水浏览/手动调额/额度策略CRUD+拦截

后端:adminpanel ledgers(全局流水+筛)+ adjust(手动调额,落 ADJUSTMENT)+ quota-policies CRUD;
额度拦截 _enforce_quota_policy(单任务/月度/项目)接入 reserve_credit,仅团队有 active 策略才生效(无策略零回归);
adjust_credit helper。修真 bug:log_admin_action 加 savepoint + JSON 安全化(UUID/Decimal),
修复传 serializer.data 致审计报错污染外层事务 → TransactionManagementError。
前端:adminApi 计费/额度系列;计费审计页(流水表+手动调额弹窗)+ 额度策略页(CRUD 弹窗,团队下拉+三类上限+启用)。
测试:adminpanel 44 + billing + accounts = 70 单测过(调额±/超额拒/额度拦截 per_task+monthly/无策略零回归);
无头 e2e _admin-p7.mjs 6 断言过 + 0 console error(一次性团队,不动 demo 余额);tsc+build 绿。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

core/backend/apps/billing/services/ledger.py

@@ -4,7 +4,7 @@ from django.db import transaction
 from django.db.models import Sum
 from django.utils import timezone
 
-from apps.billing.models import CreditAccount, CreditLedger, CreditReservation
+from apps.billing.models import CreditAccount, CreditLedger, CreditReservation, QuotaPolicy
 
 
 def _enforce_member_monthly_limit(*, team, user, amount: Decimal) -> None:
@@ -34,6 +34,65 @@ def _enforce_member_monthly_limit(*, team, user, amount: Decimal) -> None:
         raise ValueError(f"成员本月额度不足:限额 ¥{limit},本月已用 ¥{charged}(另有在途 ¥{reserved})")
 
 
+def _enforce_quota_policy(*, team, project, amount: Decimal) -> None:
+    """平台 4 层额度策略(QuotaPolicy)。**仅当团队存在 active 团队级策略时才生效** ——
+    无策略的团队行为完全不变(零回归)。检查 单任务 / 团队月度 / 项目 三类限额(任一为 None 即该维度不限)。"""
+    policy = (
+        team.quota_policies.filter(is_active=True, user__isnull=True, project__isnull=True)
+        .order_by("-created_at")
+        .first()
+    )
+    if policy is None:
+        return
+    if policy.per_task_limit is not None and amount > policy.per_task_limit:
+        raise ValueError(f"单任务额度超限:上限 ¥{policy.per_task_limit}")
+    now = timezone.now()
+    month_start = now.replace(day=1, hour=0, minute=0, second=0, microsecond=0)
+    if policy.monthly_limit is not None:
+        charged = (
+            CreditLedger.objects.filter(team=team, ledger_type=CreditLedger.Type.CHARGE, created_at__gte=month_start)
+            .aggregate(s=Sum("amount"))["s"] or Decimal("0")
+        )
+        reserved = (
+            CreditReservation.objects.filter(team=team, status=CreditReservation.Status.ACTIVE)
+            .aggregate(s=Sum("amount"))["s"] or Decimal("0")
+        )
+        if charged + reserved + amount > policy.monthly_limit:
+            raise ValueError(f"团队本月额度超限:上限 ¥{policy.monthly_limit}")
+    if policy.project_limit is not None and project is not None:
+        p_charged = (
+            CreditLedger.objects.filter(team=team, project=project, ledger_type=CreditLedger.Type.CHARGE)
+            .aggregate(s=Sum("amount"))["s"] or Decimal("0")
+        )
+        p_reserved = (
+            CreditReservation.objects.filter(team=team, project=project, status=CreditReservation.Status.ACTIVE)
+            .aggregate(s=Sum("amount"))["s"] or Decimal("0")
+        )
+        if p_charged + p_reserved + amount > policy.project_limit:
+            raise ValueError(f"项目额度超限:上限 ¥{policy.project_limit}")
+
+
+@transaction.atomic
+def adjust_credit(*, team, amount: Decimal, reason: str = "", operator=None) -> CreditLedger:
+    """平台超管手动调额(争议 / 补偿)。amount 可正可负;落 ADJUSTMENT 流水并更新余额。
+    调额后余额不得为负(否则拒绝)。"""
+    account, _ = CreditAccount.objects.select_for_update().get_or_create(team=team)
+    new_balance = account.balance + amount
+    if new_balance < 0:
+        raise ValueError("调额后余额为负,已拒绝")
+    account.balance = new_balance
+    account.save(update_fields=["balance", "updated_at"])
+    return CreditLedger.objects.create(
+        team=team,
+        user=operator,
+        ledger_type=CreditLedger.Type.ADJUSTMENT,
+        amount=amount,
+        balance_after=new_balance,
+        reason=reason or "平台手动调额",
+        metadata={"kind": "admin_adjust"},
+    )
+
+
 @transaction.atomic
 def reserve_credit(*, team, user, task, amount: Decimal) -> CreditReservation:
     account, _ = CreditAccount.objects.select_for_update().get_or_create(team=team)
@@ -41,6 +100,7 @@ def reserve_credit(*, team, user, task, amount: Decimal) -> CreditReservation:
     if available < amount:
         raise ValueError("insufficient credit")
     _enforce_member_monthly_limit(team=team, user=user, amount=amount)
+    _enforce_quota_policy(team=team, project=task.project, amount=amount)
 
     account.reserved_balance += amount
     account.save(update_fields=["reserved_balance", "updated_at"])