[Refactor] Cuda Graph Runner/Backend Refactor (#23906)

Co-authored-by: BBuf <1182563586@qq.com>
Co-authored-by: Cheng Wan <54331508+ch-wan@users.noreply.github.com>
Co-authored-by: Lianmin Zheng <lianminzheng@gmail.com>

test/registered/debug_utils/test_engine_dumper_comparator_e2e.py

@@ -325,7 +325,7 @@ def _run_server_and_generate(
         "--mem-fraction-static",
         "0.5",
         "--disable-cuda-graph",
-        "--disable-piecewise-cuda-graph",
+        "--cuda-graph-backend-prefill=disabled",
         "--disable-radix-cache",
     ]
     if extra_server_args: