feat: migrate SGLang configuration (ai-dynamo#6280)

Signed-off-by: jh-nv <[email protected]>

Author: jh-nv

components/src/dynamo/common/configuration/groups/runtime_args.py

@@ -15,6 +15,7 @@ class DynamoRuntimeConfig(ConfigBase):
     """Configuration for Dynamo runtime (common across all backends)."""
 
     namespace: str
+    endpoint: Optional[str] = None
     discovery_backend: str
     request_plane: str
     event_plane: str
@@ -52,6 +53,13 @@ def add_arguments(self, parser) -> None:
             default="dynamo",
             help="Dynamo namespace",
         )
+        add_argument(
+            g,
+            flag_name="--endpoint",
+            env_var="DYN_ENDPOINT",
+            default=None,
+            help="Dynamo endpoint string in 'dyn://namespace.component.endpoint' format. Example: dyn://dynamo.backend.generate. Currently used only by TRT-LLM and SGLang backends.",
+        )
         add_argument(
             g,
             flag_name="--discovery-backend",