chore: import Local-Cursor v1.1.8 source snapshot

Includes the current working directory changes. Historical commits and release binaries are excluded to limit Gitea storage.
Source base: d7515973fbfd6dd2001fa156c483455b8081c7cb

internal/backend/agent/model/provider_limits.go

@@ -0,0 +1,58 @@
+package modeladapter
+
+import (
+	"regexp"
+	"strconv"
+)
+
+func maxAnthropicTokens(req StreamRequest) int {
+	if req.AnthropicMaxTokens > 0 {
+		return req.AnthropicMaxTokens
+	}
+	if req.MaxTokens > 0 {
+		return req.MaxTokens
+	}
+	return 65536
+}
+
+// anthropicOutputLimitPattern 匹配 one-api/new-api 风格网关在 max_tokens 超限时的 400 错误：
+// "Requested token count exceeds the configured maximum output length of 131072 tokens."
+var anthropicOutputLimitPattern = regexp.MustCompile(`exceeds the configured maximum output length of (\d+) tokens`)
+
+// anthropicOutputLimitFromError 从网关错误文本中提取其声明的最大输出上限；不匹配或解析失败返回 0。
+func anthropicOutputLimitFromError(err error) int {
+	if err == nil {
+		return 0
+	}
+	matches := anthropicOutputLimitPattern.FindStringSubmatch(err.Error())
+	if len(matches) < 2 {
+		return 0
+	}
+	limit, parseErr := strconv.Atoi(matches[1])
+	if parseErr != nil || limit <= 0 {
+		return 0
+	}
+	return limit
+}
+
+// anthropicBodyMaxTokens 读取既有请求体中实际发送的 max_tokens；
+// 常规构造为 int，RequestBodyOverride 反序列化产物为 float64，两者都兼容。
+func anthropicBodyMaxTokens(body map[string]any) int {
+	switch value := body["max_tokens"].(type) {
+	case int:
+		return value
+	case int64:
+		return int(value)
+	case float64:
+		return int(value)
+	default:
+		return 0
+	}
+}
+
+func maxThinkingBudget(req StreamRequest) int {
+	if req.ThinkingBudgetTokens > 0 {
+		return req.ThinkingBudgetTokens
+	}
+	return anthropicThinkingBudget(maxAnthropicTokens(req))
+}