feat: 新增 LLM checker 支持大模型服务应用层拨测

基于 AI SDK v6 实现 openai/openai-responses/anthropic 三类 provider 的 http/stream 模式调用
支持 output/finishReason/usage/stream 等完整 expect 断言链路
新增 9 个源文件和 5 个测试文件共 78 个测试
更新 README/DEVELOPMENT/probes.example.yaml 和 probe-config.schema.json

package.json

@@ -46,10 +46,13 @@
     "vite": "^8.0.13"
   },
   "dependencies": {
+    "@ai-sdk/anthropic": "^3",
+    "@ai-sdk/openai": "^3",
     "@number-flow/react": "^0.6.0",
     "@sinclair/typebox": "^0.34.49",
     "@tanstack/react-query": "^5.100.10",
     "@xmldom/xmldom": "^0.9.10",
+    "ai": "^6",
     "ajv": "^8.20.0",
     "cheerio": "^1.2.0",
     "es-toolkit": "^1.46.1",