refactor(llmx-impl-openai): 重构 OpenAI 模型服务和响应处理

- 优化 OpenAiModelServiceImpl 中的 JSON 解析逻辑
- 修改 SseEvent 数据类，将 data 字段改为 response
- 调整响应处理逻辑，以适应新的数据结构

llmx-impl/llmx-impl-openai/src/main/kotlin/org/jcnc/llmx/impl/openai/config/service/impl/OpenAiModelServiceImpl.kt

@@ -54,19 +54,20 @@ class OpenAiModelServiceImpl(
             extractContent = { json ->
                 val node = objectMapper.readTree(json)
                 val type = node["type"]?.asText()
-
+                val response = node["response"]
+                val data = response ?: node
                 when (type) {
                     "response.output_text.delta" -> {
-                        val outputTextDelta = objectMapper.treeToValue(node, OutputTextDelta::class.java)
+                        val outputTextDelta = objectMapper.treeToValue(data, OutputTextDelta::class.java)
                         ChatResponsePart(content = outputTextDelta.delta)
                     }
 
                     "response.output_text.done" -> {
-                        val outputTextDone = objectMapper.treeToValue(node, OutputTextDone::class.java)
+                        val outputTextDone = objectMapper.treeToValue(data, OutputTextDone::class.java)
                         ChatResponsePart(content = outputTextDone.text, done = true)
                     }
                     "response.completed" -> {
-                        val completed = objectMapper.treeToValue(node, FullResponse::class.java)
+                        val completed = objectMapper.treeToValue(data, FullResponse::class.java)
                         val usage = completed.usage?.let {
                             Usage(
                                 promptTokens = it.inputTokens ?: 0,

llmx-impl/llmx-impl-openai/src/main/kotlin/org/jcnc/llmx/impl/openai/entities/response/OpenAiMultimodalityChatReposponse.kt

@@ -6,8 +6,8 @@ import com.fasterxml.jackson.annotation.JsonProperty
 data class SseEvent<T>(
     @JsonProperty("type")
     val type: String,
-    @JsonProperty("data")
-    val data: T
+    @JsonProperty("response")
+    val response: T
 )
 
 /** response.created, response.in_progress, response.completed 共用结构 */