feat(billing): 计费商业化重构(积分制)+ 团队差异化调价

统一计价引擎 apps/billing/pricing.py:1积分=¥0.1,平台成本(¥)与用户价(积分)双记账,
视频按火山真实 usage.total_tokens 结算(true-up,终结¥1/段倒贴)+ 首发×1.5毛利系数。
Team.price_multiplier 差异化调价(jimeng同款):挂牌价×系数两步HALF_UP取整,视频类
按下单时的价格/汇率快照结算(中途改配不影响在途任务)。

BillingConfig 单例(汇率/毛利系数/预留buffer,admin可调即刻生效)。存量数据 ×10 rescale
迁移(RunPython+atomic,MySQL 迁移不可中断重跑)。开户赠送归零(DEFAULT_TRIAL_CREDITS=0,
商业决策)。audit_billing 加 I9(卖亏审计)。271 条测试 + tsc/build 全绿。

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

core/backend/apps/ai/free_video.py

@@ -15,7 +15,6 @@ import logging
 import re
 import uuid
 from datetime import timedelta
-from decimal import Decimal, ROUND_HALF_UP
 from io import BytesIO
 
 from django.conf import settings
@@ -25,17 +24,13 @@ from django.utils import timezone
 
 from apps.assets.models import Asset, AssetFile, FreeAsset, FreeAssetGroup
 from apps.assets.storage import TosStorage
+from apps.billing.pricing import quote_video_actual, quote_video_estimate, video_reserve_amount
 from apps.billing.services.ledger import charge_reserved_credit, release_credit, reserve_credit
 
 from .models import AITask, ModelConfig
 from .providers.volcano import VolcanoArkProvider
 from .video_errors import map_video_error, parse_provider_error
-from .video_pricing import (
-    RESERVE_BUFFER,
-    estimate_video_cost,
-    get_resolution,
-    tokens_to_cost,
-)
+from .video_pricing import get_resolution
 
 logger = logging.getLogger(__name__)
 
@@ -372,14 +367,16 @@ def submit_free_video(*, team, user, params: dict) -> AITask:
 
     built = build_content_items(team=team, prompt=prompt, mode=mode, references=references)
 
-    tokens, cost = estimate_video_cost(
+    # 统一计价引擎:¥成本 × 毛利系数 → 积分;预留 = 积分 × buffer(均为 BillingConfig 可配)
+    tokens, quote = quote_video_estimate(
         model_config,
         aspect_ratio=aspect_ratio,
         resolution=resolution,
         duration=duration,
         references=built["snapshots"],
+        team=team,
     )
-    reserve_amount = (cost * RESERVE_BUFFER).quantize(Decimal("0.01"), rounding=ROUND_HALF_UP)
+    reserve_amount = video_reserve_amount(quote.points)
 
     request_payload = {
         "feature": "free_video",
@@ -395,6 +392,9 @@ def submit_free_video(*, team, user, params: dict) -> AITask:
         "generate_audio": generate_audio,
         "search_mode": search_mode,
         "estimated_tokens": tokens,
+        # 团队价格系数快照:按实结算用它,中途改价不影响在途任务
+        "price_multiplier": quote.meta.get("price_multiplier", "1"),
+        "points_per_yuan_snapshot": quote.meta.get("rate", ""),
         "references": built["snapshots"],
     }
 
@@ -409,7 +409,8 @@ def submit_free_video(*, team, user, params: dict) -> AITask:
             model_config=model_config,
             idempotency_key=f"free_video:{team.id}:{uuid.uuid4()}",
             request_payload=request_payload,
-            estimated_cost=cost,
+            estimated_cost=quote.points,
+            base_cost=quote.base_cost_yuan,
         )
         try:
             reserve_credit(team=team, user=user, task=task, amount=reserve_amount)
@@ -619,12 +620,18 @@ def finalize_free_video(*, task: AITask) -> AITask:
         with_video_ref = any((r or {}).get("type") == "video" for r in payload.get("references") or [])
         resolution = payload.get("resolution") or "720p"
         if total_tokens > 0:
-            actual = tokens_to_cost(
-                locked.model_config, total_tokens, with_video_ref=with_video_ref, resolution=resolution
+            from decimal import Decimal
+
+            settle = quote_video_actual(
+                locked.model_config, tokens=total_tokens, with_video_ref=with_video_ref, resolution=resolution,
+                multiplier=Decimal(str(payload.get("price_multiplier") or "1")),
             )
+            actual, base_cost = settle.points, settle.base_cost_yuan
             payload["actual_tokens"] = total_tokens
+            if settle.meta.get("rate"):
+                payload["points_per_yuan_snapshot"] = settle.meta["rate"]
         else:
-            actual = locked.estimated_cost
+            actual, base_cost = locked.estimated_cost, locked.base_cost
         seed_out = response.get("seed")
         if seed_out is not None:
             payload["seed_used"] = seed_out
@@ -635,7 +642,7 @@ def finalize_free_video(*, task: AITask) -> AITask:
                 return locked
             reservation = locked.credit_reservation
             if actual > reservation.amount:
-                # ledger 禁超预留扣费 → clamp 到预留额,差额平台承担并告警(长期观测调 RESERVE_BUFFER)
+                # ledger 禁超预留扣费 → clamp 到预留额,差额平台承担并告警(长期观测调 buffer)
                 logger.warning(
                     "free video task %s actual cost %s exceeds reserved %s, clamped",
                     locked.id, actual, reservation.amount,
@@ -643,11 +650,12 @@ def finalize_free_video(*, task: AITask) -> AITask:
                 actual = reservation.amount
             locked.status = AITask.Status.SUCCEEDED
             locked.actual_cost = actual
+            locked.base_cost = base_cost
             locked.request_payload = payload
             locked.response_payload = response
             locked.completed_at = timezone.now()
             locked.save(
-                update_fields=["status", "actual_cost", "request_payload", "response_payload", "completed_at", "updated_at"]
+                update_fields=["status", "actual_cost", "base_cost", "request_payload", "response_payload", "completed_at", "updated_at"]
             )
             charge_reserved_credit(reservation=reservation, actual_amount=actual)
         return locked