feat: add Doubao Global web search provider (#92)

api-providers/web-search/doubao-search-global.json

@@ -0,0 +1,36 @@
+{
+  "id": "doubao-search-global",
+  "name": "豆包搜索 Global",
+  "capability": "web_search",
+  "enabled": false,
+  "builtin": true,
+  "priority": 40,
+  "endpoint": "https://open.feedcoopapi.com/search_api/global_search",
+  "method": "POST",
+  "auth": {
+    "type": "bearer",
+    "apiKeyRef": "doubao-search-global"
+  },
+  "request": {
+    "bodyTemplate": {
+      "Query": "${query}",
+      "SearchType": "web",
+      "DocCount": "${maxResults}",
+      "MaxSnippetLength": 500
+    }
+  },
+  "response": {
+    "resultsPath": "Result.Documents",
+    "item": {
+      "titlePath": "Title",
+      "urlPath": "Url",
+      "snippetPath": "Snippet.0.Text",
+      "pageAgePath": "DocumentInfo.PublishTime"
+    },
+    "successCondition": {
+      "path": "Result.ErrorCode",
+      "equals": 0
+    }
+  },
+  "timeoutMs": 10000
+}