[Lint] Add python/sglang to ruff F401 checks and remove unused imports in files (#11685)

python/sglang/srt/grpc/compile_proto.py

@@ -70,7 +70,7 @@ def compile_proto(proto_file: Path, output_dir: Path, verbose: bool = True) -> b
 
     # Check if grpc_tools is available
     try:
-        import grpc_tools.protoc
+        import grpc_tools.protoc  # noqa: F401
     except ImportError:
         print("Error: grpcio-tools not installed")
         print(

python/sglang/srt/grpc/grpc_request_manager.py

@@ -27,7 +27,6 @@ from sglang.srt.managers.io_struct import (
     TokenizedEmbeddingReqInput,
     TokenizedGenerateReqInput,
 )
-from sglang.srt.managers.scheduler import is_health_check_generate_req
 from sglang.srt.server_args import PortArgs, ServerArgs
 from sglang.srt.utils import get_zmq_socket, kill_process_tree
 from sglang.utils import get_exception_traceback