[v1] support ulysses cp for fsdp2 (#10262)

examples/v1/train_full/train_full_ulysses_cp.yaml

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+model: Qwen/Qwen3-0.6B
+trust_remote_code: true
+model_class: llm
+
+template: qwen3_nothink
+
+# FSDP Config
+dist_config:
+  name: fsdp2
+  dcp_path: null
+  cp_mode: ulysses
+  cp_size: 2
+
+### data
+train_dataset: data/v1_sft_demo.yaml
+
+### training
+output_dir: outputs/test_ulysses_cp
+micro_batch_size: 1
+cutoff_len: 2048
+learning_rate: 1.0e-4
+bf16: false
+max_steps: 10