feat(release): migrate GeekAI v4.3.0 to open source

- Sync backend and frontend from GeekAI Plus v4.3.0

- Remove commercial License flows and update open-source deployment defaults

- Preserve Docker Compose deployment and bump image tags to v4.3.0

BREAKING CHANGE: commercial License configuration and related endpoints are removed

api/utils/openai.go

@@ -14,6 +14,7 @@ import (
 	"geekai/store/model"
 	"io"
 	"net/url"
+	"strings"
 	"time"
 
 	"github.com/imroc/req/v3"
@@ -35,18 +36,63 @@ func CalcTokens(text string, model string) (int, error) {
 	return len(token), nil
 }
 
+// OpenAIResponse 非流式 chat/completions 响应；content 使用 RawMessage 以兼容 string 与多段式数组。
 type OpenAIResponse struct {
 	Model   string `json:"model"`
 	Choices []struct {
 		Index   int `json:"index"`
 		Message struct {
-			Role    string `json:"role"`
-			Content string `json:"content"`
+			Role    string          `json:"role"`
+			Content json.RawMessage `json:"content"`
 		} `json:"message"`
 		FinishReason string `json:"finish_reason"`
 	} `json:"choices"`
 }
 
+// assistantContentPart 兼容 OpenAI 多模态 / 多段文本：{"type":"text","text":"..."} 等。
+type assistantContentPart struct {
+	Type string `json:"type"`
+	Text string `json:"text"`
+	// 少数网关使用 content 字段承载文本
+	Inner string `json:"content"`
+}
+
+// NormalizeAssistantContent 将 message.content 规范为纯文本。
+// 兼容：JSON string、null、OpenAI 数组段、以及单段对象。
+func NormalizeAssistantContent(raw json.RawMessage) string {
+	s := strings.TrimSpace(string(raw))
+	if s == "" || s == "null" {
+		return ""
+	}
+	var plain string
+	if err := json.Unmarshal(raw, &plain); err == nil {
+		return plain
+	}
+	var parts []assistantContentPart
+	if err := json.Unmarshal(raw, &parts); err == nil && len(parts) > 0 {
+		var b strings.Builder
+		for _, p := range parts {
+			switch {
+			case p.Text != "":
+				b.WriteString(p.Text)
+			case p.Inner != "" && p.Type != "image_url" && p.Type != "image":
+				b.WriteString(p.Inner)
+			}
+		}
+		return b.String()
+	}
+	var one assistantContentPart
+	if err := json.Unmarshal(raw, &one); err == nil {
+		if one.Text != "" {
+			return one.Text
+		}
+		if one.Inner != "" {
+			return one.Inner
+		}
+	}
+	return ""
+}
+
 func OpenAIRequest(db *gorm.DB, prompt string, modelId int) (string, error) {
 	messages := make([]any, 1)
 	messages[0] = types.Message{
@@ -86,12 +132,16 @@ func SendOpenAIMessage(db *gorm.DB, messages []any, modelId int) (string, error)
 		apiURL = apiKey.ApiURL
 	}
 	logger.Infof("Sending %s request, API KEY:%s, PROXY: %s, Model: %s", apiURL, apiKey.ApiURL, apiKey.ProxyURL, chatModel.Name)
-	r, err := client.R().SetHeader("Body-Type", "application/json").
+	r, err := client.R().
+		SetHeader("Content-Type", "application/json").
 		SetHeader("Authorization", "Bearer "+apiKey.Value).
 		SetBody(types.ApiRequest{
 			Model:       chatModel.Value,
 			Temperature: 0.9,
-			MaxTokens:   1024,
+			// gpt-5/o 系模型在复杂提示下可能先消耗大量 token 于推理过程，
+			// 1024 容易导致 finish_reason=length 且 content 为空。
+			MaxTokens:           4096,
+			MaxCompletionTokens: 4096,
 			Stream:      false,
 			Messages:    messages,
 		}).Post(apiURL)
@@ -108,9 +158,17 @@ func SendOpenAIMessage(db *gorm.DB, messages []any, modelId int) (string, error)
 	if err != nil {
 		return "", fmt.Errorf("解析API数据失败：%v, %s", err, string(body))
 	}
+	if len(response.Choices) == 0 {
+		return "", fmt.Errorf("模型返回 choices 为空：%s", string(body))
+	}
+
+	out := strings.TrimSpace(NormalizeAssistantContent(response.Choices[0].Message.Content))
+	if out == "" {
+		return "", fmt.Errorf("模型返回内容为空，请重试或更换模型（若使用推理模型，请确认网关已返回 content 或 reasoning_content）")
+	}
 
 	// 更新 API KEY 的最后使用时间
 	db.Model(&apiKey).UpdateColumn("last_used_at", time.Now().Unix())
 
-	return response.Choices[0].Message.Content, nil
+	return out, nil
 }