fix: handle thinking content in Ollama chat responses

Ollama API returns reasoning model output in Message.Thinking field,
but OllamaChat only reads Message.Content. Add thinking content
handling for both streaming and non-streaming, consistent with
RemoteAPIChat behavior.

Author: is-Xiaoen

internal/models/chat/ollama.go

@@ -105,6 +105,10 @@ func (c *OllamaChat) Chat(ctx context.Context, messages []Message, opts *ChatOpt
 	// 使用 Ollama 客户端发送请求
 	err := c.ollamaService.Chat(ctx, chatReq, func(resp ollamaapi.ChatResponse) error {
 		responseContent = resp.Message.Content
+		// 当 Content 为空但 Thinking 有内容时（如推理模型未正确配置 thinking 参数），使用 Thinking 作为兜底
+		if responseContent == "" && resp.Message.Thinking != "" {
+			responseContent = resp.Message.Thinking
+		}
 		toolCalls = c.toolCallTo(resp.Message.ToolCalls)
 
 		// 获取token计数
@@ -159,8 +163,27 @@ func (c *OllamaChat) ChatStream(
 	go func() {
 		defer close(streamChan)
 
+		hasThinking := false
 		err := c.ollamaService.Chat(ctx, chatReq, func(resp ollamaapi.ChatResponse) error {
+			// 发送思考内容（支持 Qwen3、DeepSeek 等推理模型）
+			if resp.Message.Thinking != "" {
+				hasThinking = true
+				streamChan <- types.StreamResponse{
+					ResponseType: types.ResponseTypeThinking,
+					Content:      resp.Message.Thinking,
+					Done:         false,
+				}
+			}
+
 			if resp.Message.Content != "" {
+				// 思考阶段结束后，发送思考完成事件
+				if hasThinking {
+					streamChan <- types.StreamResponse{
+						ResponseType: types.ResponseTypeThinking,
+						Done:         true,
+					}
+					hasThinking = false
+				}
 				streamChan <- types.StreamResponse{
 					ResponseType: types.ResponseTypeAnswer,
 					Content:      resp.Message.Content,