feat: support xAI Grok Live Search config (#3203)

* Add xai_native_search configuration option

* Implement xAI compatibility and search injection

Add support for xAI integration with search parameters injection.

* Refactor xAI handling in openai_source.py

Removed the _is_xai method and updated xAI search injection logic.

* Fix formatting of condition in default.py

* Fix formatting in openai_source.py

astrbot/core/config/default.py

@@ -771,6 +771,7 @@ CONFIG_METADATA_2 = {
                         "timeout": 120,
                         "model_config": {"model": "grok-2-latest", "temperature": 0.4},
                         "custom_extra_body": {},
+                        "xai_native_search": False,
                         "modalities": ["text", "image", "tool_use"],
                     },
                     "Anthropic": {
@@ -1288,6 +1289,12 @@ CONFIG_METADATA_2 = {
                     },
                 },
                 "items": {
+                    "xai_native_search": {
+                        "description": "启用原生搜索功能",
+                        "type": "bool",
+                        "hint": "启用后，将通过 xAI 的 Chat Completions 原生 Live Search 进行联网检索（按需计费）。仅对 xAI 提供商生效。",
+                        "condition": {"provider": "xai"},
+                    },
                     "rerank_api_base": {
                         "description": "重排序模型 API Base URL",
                         "type": "string",

astrbot/core/provider/sources/openai_source.py

@@ -68,6 +68,28 @@ class ProviderOpenAIOfficial(Provider):
         model = model_config.get("model", "unknown")
         self.set_model(model)
 
+    def _maybe_inject_xai_search(self, payloads: dict, **kwargs):
+        """当开启 xAI 原生搜索时，向请求体注入 Live Search 参数。
+
+        - 仅在 provider_config.xai_native_search 为 True 时生效
+        - 默认注入 {"mode": "auto"}
+        - 允许通过 kwargs 使用 xai_search_mode 覆盖（on/auto/off）
+        """
+        if not bool(self.provider_config.get("xai_native_search", False)):
+            return
+
+        mode = kwargs.get("xai_search_mode", "auto")
+        mode = str(mode).lower()
+        if mode not in ("auto", "on", "off"):
+            mode = "auto"
+
+        # off 时不注入，保持与未开启一致
+        if mode == "off":
+            return
+
+        # OpenAI SDK 不识别的字段会在 _query/_query_stream 中放入 extra_body
+        payloads["search_parameters"] = {"mode": mode}
+
     async def get_models(self):
         try:
             models_str = []
@@ -271,6 +293,9 @@ class ProviderOpenAIOfficial(Provider):
 
         payloads = {"messages": context_query, **model_config}
 
+        # xAI 原生搜索参数（最小侵入地在此处注入）
+        self._maybe_inject_xai_search(payloads, **kwargs)
+
         return payloads, context_query
 
     async def _handle_api_error(