feat: 算力引擎 Go 后端核心（new-api）

- 统一 OpenAI 兼容 /v1 中继 + 渠道/额度/令牌/流水
- 各领域包：relay 模型网关、model 数据层、controller 管理 API

setting/operation_setting/operation_setting.go

@@ -0,0 +1,32 @@
+package operation_setting
+
+import "strings"
+
+var DemoSiteEnabled = false
+var SelfUseModeEnabled = false
+
+var AutomaticDisableKeywords = []string{
+	"Your credit balance is too low",
+	"This organization has been disabled.",
+	"You exceeded your current quota",
+	"Permission denied",
+	"The security token included in the request is invalid",
+	"Operation not allowed",
+	"Your account is not authorized",
+}
+
+func AutomaticDisableKeywordsToString() string {
+	return strings.Join(AutomaticDisableKeywords, "\n")
+}
+
+func AutomaticDisableKeywordsFromString(s string) {
+	AutomaticDisableKeywords = []string{}
+	ak := strings.Split(s, "\n")
+	for _, k := range ak {
+		k = strings.TrimSpace(k)
+		k = strings.ToLower(k)
+		if k != "" {
+			AutomaticDisableKeywords = append(AutomaticDisableKeywords, k)
+		}
+	}
+}