fix sse/streamable compatible issue by change mcp_router.py and update config.yaml.example

Author: songyichun123

config.yaml.example

@@ -41,7 +41,7 @@ tool:
     url: #mcp sse url
     dataset_id:  #dataset name
   mcp_router:
-    url: #mcp sse url
+    url: #mcp sse/streamable-http url
 
 
 observability:

veadk/tools/builtin_tools/mcp_router.py

@@ -12,10 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from google.adk.tools.mcp_tool.mcp_toolset import MCPToolset, SseConnectionParams
+from google.adk.tools.mcp_tool.mcp_toolset import MCPToolset
 
 from veadk.config import getenv
+from veadk.utils.mcp_utils import get_mcp_params
 
 url = getenv("TOOL_MCP_ROUTER_URL")
 
-mcp_router = MCPToolset(connection_params=SseConnectionParams(url=url))
+mcp_router = MCPToolset(connection_params=get_mcp_params(url=url))