[Frontend][4/N] Improve all pooling task | Add plugin pooling task (#26973)

Signed-off-by: wang.yuqi <noooop@126.com>
Signed-off-by: Christian Pinto <christian.pinto@ibm.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Christian Pinto <christian.pinto@ibm.com>

vllm/entrypoints/openai/api_server.py

@@ -1748,7 +1748,12 @@ async def init_app_state(
                 log_error_stack=args.log_error_stack,
             )
         )
-        if ("token_embed" in supported_tasks or "token_classify" in supported_tasks)
+        if (
+            any(
+                task in supported_tasks
+                for task in ["token_embed", "token_classify", "plugin"]
+            )
+        )
         else None
     )
     state.openai_serving_embedding = (