[Fix] self.worker assignment in TpModelWorker and refactor references (#4788)

Signed-off-by: Xinyuan Tong <justinning0323@outlook.com>

python/sglang/srt/managers/scheduler.py

@@ -1703,18 +1703,12 @@ class Scheduler(
     def save_remote_model(self, params):
         url = params["url"]
 
-        if isinstance(self.tp_worker, TpModelWorkerClient):
-            worker = self.tp_worker.worker
-        else:
-            worker = self.tp_worker
+        worker = self.tp_worker.worker
 
         worker.model_runner.save_remote_model(url)
 
     def save_sharded_model(self, params):
-        if isinstance(self.tp_worker, TpModelWorkerClient):
-            worker = self.tp_worker.worker
-        else:
-            worker = self.tp_worker
+        worker = self.tp_worker.worker
 
         worker.model_runner.save_sharded_model(
             path=params["path"],

python/sglang/srt/managers/tp_worker.py

@@ -53,6 +53,8 @@ class TpModelWorker:
         req_to_token_pool: Optional[ReqToTokenPool] = None,
         token_to_kv_pool_allocator: Optional[TokenToKVPoolAllocator] = None,
     ):
+        self.worker = self
+
         # Parse args
         self.tp_rank = tp_rank