feat(provider): add lmstudio and align local provider default auth/base handling (#2193)

* feat(provider): add lmstudio vendor and local no-key behavior

* refactor(provider): consolidate protocol metadata and local tests

* fix(provider): sync lmstudio probing and model normalization

* test(web): format lmstudio model status cases for golines

config/config.example.json

@@ -48,6 +48,10 @@
       "model": "deepseek/deepseek-chat",
       "api_key": "sk-your-deepseek-key"
     },
+    {
+      "model_name": "lmstudio-local",
+      "model": "lmstudio/openai/gpt-oss-20b"
+    },
     {
       "model_name": "longcat",
       "model": "longcat/LongCat-Flash-Thinking",