Fix review blockers and cleanup for PR merge

- Fix blocking urlopen in async GET /api/config/model via asyncio.to_thread
- Fix LM Studio use_raw_model_name sending prefixed model id to API
- Fix _is_anthropic_model matching openrouter/anthropic/ routes
- Add message-count limit (2000) on restore-session-summary
- Add provider config check on model switch (openai-compat/ env guard)
- Cache _all_adapter_prefixes with lru_cache
- Extract useModelCatalog hook from ChatInput (635 -> 528 lines)
- Memoize provider groups calculation
- Add Enter key support to CustomModelDialog
- Fix useEffect dependency loop on selectedModelInfo

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: andrejvysny

agent/core/provider_adapters.py

@@ -1,5 +1,6 @@
 """Provider adapters for runtime params and model catalog metadata."""
 
+import functools
 import json
 import os
 import time
@@ -64,6 +65,7 @@ def _provider_avatar_url(provider_id: str) -> str:
     return avatars.get(provider_id, "https://huggingface.co/api/avatars/huggingface")
 
 
+@functools.lru_cache(maxsize=1)
 def _all_adapter_prefixes() -> tuple[str, ...]:
     prefixes: list[str] = []
     for adapter in ADAPTERS:
@@ -396,7 +398,7 @@ def build_params(
 
         model_id = model_name.removeprefix(self.prefixes[0])
         params: dict[str, Any] = {
-            "model": model_name if self.use_raw_model_name else f"openai/{model_id}",
+            "model": model_id if self.use_raw_model_name else f"openai/{model_id}",
             "api_base": self.resolved_api_base(),
             "api_key": self.resolved_api_key(),
         }

backend/routes/agent.py

@@ -34,15 +34,19 @@
 
 from agent.core.llm_errors import health_error_type, render_llm_error_message
 from agent.core.llm_params import _resolve_llm_params
-from agent.core.provider_adapters import build_model_catalog, is_valid_model_name
+from agent.core.provider_adapters import (
+    build_model_catalog,
+    is_valid_model_name,
+    resolve_adapter,
+)
 
 logger = logging.getLogger(__name__)
 
 router = APIRouter(prefix="/api", tags=["agent"])
 
 
 def _is_anthropic_model(model_id: str) -> bool:
-    return "anthropic" in model_id
+    return model_id.startswith(("anthropic/", "bedrock/"))
 
 
 async def _require_hf_for_anthropic(request: Request, model_id: str) -> None:
@@ -162,7 +166,9 @@ async def llm_health_check() -> LLMHealthResponse:
 @router.get("/config/model")
 async def get_model() -> dict:
     """Get current model and available models. No auth required."""
-    return build_model_catalog(session_manager.config.model_name)
+    return await asyncio.to_thread(
+        build_model_catalog, session_manager.config.model_name
+    )
 
 
 _TITLE_STRIP_CHARS = str.maketrans("", "", "`*_~#[]()")
@@ -290,6 +296,8 @@ async def restore_session_summary(
     messages = body.get("messages")
     if not isinstance(messages, list) or not messages:
         raise HTTPException(status_code=400, detail="Missing 'messages' array")
+    if len(messages) > 2000:
+        raise HTTPException(status_code=400, detail="Too many messages (max 2000)")
 
     hf_token = None
     auth_header = request.headers.get("Authorization", "")
@@ -361,6 +369,11 @@ async def set_session_model(
         raise HTTPException(status_code=400, detail="Missing 'model' field")
     if not is_valid_model_name(model_id):
         raise HTTPException(status_code=400, detail=f"Unknown model: {model_id}")
+    adapter = resolve_adapter(model_id)
+    if adapter and not adapter.should_show():
+        raise HTTPException(
+            status_code=400, detail=f"Provider not configured for: {model_id}"
+        )
     await _require_hf_for_anthropic(request, model_id)
     agent_session = session_manager.sessions.get(session_id)
     if not agent_session: