Merge origin/main into nightly

Resolve conflicts:
- .gitignore: keep nightly additions (.test, skills-lock.json)
- relay/helper/price.go: keep both billingexpr and model imports
- en.json / zh-CN.json: keep nightly's superset of i18n entries
- service/billing_session.go: add missing 3rd arg to DecreaseUserQuota
- en.json / zh-CN.json: deduplicate 129+320 duplicate i18n keys

relay/helper/price.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/QuantumNous/new-api/common"
 	"github.com/QuantumNous/new-api/logger"
+	"github.com/QuantumNous/new-api/model"
 	"github.com/QuantumNous/new-api/pkg/billingexpr"
 	relaycommon "github.com/QuantumNous/new-api/relay/common"
 	"github.com/QuantumNous/new-api/setting/billing_setting"
@@ -15,6 +16,21 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
+func modelPriceNotConfiguredError(modelName string, userId int) error {
+	if model.IsAdmin(userId) {
+		return fmt.Errorf(
+			"模型 %s 的价格未配置。请前往「系统设置 → 运营设置」开启自用模式，或在「系统设置 → 分组与模型定价设置」中为该模型配置价格；"+
+				"Model %s price not configured. Go to System Settings → Operation Settings to enable self-use mode, or configure the model price in System Settings → Group & Model Pricing.",
+			modelName, modelName,
+		)
+	}
+	return fmt.Errorf(
+		"模型 %s 的价格尚未由管理员配置，暂时无法使用，请联系站点管理员开启该模型；"+
+			"Model %s has not been priced by the administrator yet. Please contact the site administrator to enable this model.",
+		modelName, modelName,
+	)
+}
+
 // https://docs.claude.com/en/docs/build-with-claude/prompt-caching#1-hour-cache-duration
 const claudeCacheCreation1hMultiplier = 6 / 3.75
 
@@ -82,7 +98,7 @@ func ModelPriceHelper(c *gin.Context, info *relaycommon.RelayInfo, promptTokens
 				acceptUnsetRatio = true
 			}
 			if !acceptUnsetRatio {
-				return types.PriceData{}, fmt.Errorf("模型 %s 倍率或价格未配置，请联系管理员设置或开始自用模式；Model %s ratio or price not set, please set or start self-use mode", matchName, matchName)
+				return types.PriceData{}, modelPriceNotConfiguredError(matchName, info.UserId)
 			}
 		}
 		completionRatio = ratio_setting.GetCompletionRatio(info.OriginModelName)
@@ -168,7 +184,7 @@ func ModelPriceHelperPerCall(c *gin.Context, info *relaycommon.RelayInfo) (types
 				acceptUnsetRatio = true
 			}
 			if !ratioSuccess && !acceptUnsetRatio {
-				return types.PriceData{}, fmt.Errorf("模型 %s 倍率或价格未配置，请联系管理员设置或开始自用模式；Model %s ratio or price not set, please set or start self-use mode", matchName, matchName)
+				return types.PriceData{}, modelPriceNotConfiguredError(matchName, info.UserId)
 			}
 		}
 	}