feat: use XGrammar V4.1 DSML parameter constraints (#39026)

Co-authored-by: yuchuan <yuchuan.7streams@gmail.com>
Co-authored-by: Xinyuan Tong <115166877+JustinTong0323@users.noreply.github.com>
Co-authored-by: Xinyuan Tong <xinyuantong.cs@gmail.com>

test/registered/dp_attn/test_dp_attention.py

@@ -50,6 +50,8 @@ class TestDPAttentionDP2TP2(
             timeout=DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
             other_args=[
                 "--trust-remote-code",
+                "--constrained-json-max-whitespace-cnt",
+                "4",
                 "--tp",
                 "2",
                 "--enable-dp-attention",