merge origin/main into pr-1071, adopt @property api_key pattern

nanobot/agent/tools/web.py

@@ -65,14 +65,13 @@ class WebSearchTool(Tool):
     def api_key(self) -> str:
         """Resolve API key at call time so env/config changes are picked up."""
         return self._init_api_key or os.environ.get("BRAVE_API_KEY", "")
-    
+
     async def execute(self, query: str, count: int | None = None, **kwargs: Any) -> str:
         if not self.api_key:
             return (
                 "Error: Brave Search API key not configured. "
-                "Set BRAVE_API_KEY environment variable or add "
-                "tools.web.search.apiKey to ~/.nanobot/config.json, "
-                "then restart the gateway."
+                "Set it in ~/.nanobot/config.json under tools.web.search.apiKey "
+                "(or export BRAVE_API_KEY), then restart the gateway."
             )
         
         try:
@@ -81,7 +80,7 @@ class WebSearchTool(Tool):
                 r = await client.get(
                     "https://api.search.brave.com/res/v1/web/search",
                     params={"q": query, "count": n},
-                    headers={"Accept": "application/json", "X-Subscription-Token": self.api_key},
+                    headers={"Accept": "application/json", "X-Subscription-Token": api_key},
                     timeout=10.0
                 )
                 r.raise_for_status()