exp: 轮次29——全拒后减半反馈到达55.1%，补齐无碰撞指标与首撞回放

512题无碰撞到达54.7%、碰撞1.8%；9次首撞均在J5限位且双精度复现。保留小样本消融，撤回未经实际调度验证的50Hz达标结论，附六项回归测试及完整配置结果。

docs/experiment_round29.json

@@ -0,0 +1,62 @@
+{
+  "config": {
+    "ckpt": "ml/runs/base_dag2_dag1/best.pt",
+    "samples": "ml/data/samples",
+    "tasks": null,
+    "split": "val",
+    "n": 512,
+    "K": 8,
+    "commit": 2,
+    "fb": 2.2,
+    "ki": 0.0,
+    "fb_scale": 0.0,
+    "fb_near": 0.2,
+    "fb_fallback": 0.0,
+    "kdecay": 0.9,
+    "kimax": 0.5,
+    "fb_every": 1,
+    "safety_try": 0,
+    "sel_w": 0.1,
+    "dls_safety": 1,
+    "fb_clear": 0.0,
+    "fb_cmin": 0.3,
+    "sub_refresh": 0,
+    "fb_block_gain": 0.5,
+    "dump": "ml/runs/round29_rows.json",
+    "out": "docs/experiment_round29.json",
+    "trace": "ml/runs/round29_trace.pt",
+    "select": "endpoint",
+    "replan": "empty",
+    "safety": 1,
+    "partial": 1,
+    "max_sec": null,
+    "seed": 0,
+    "dls": "analytic",
+    "device": "cuda"
+  },
+  "batch_size": 256,
+  "batch_seed_rule": "same seed per batch",
+  "checkpoint_sha256": "f7f686fd8ee92fb6948fbcc4ee954636065ad87bb54f661c4f8f575bc16c2ce1",
+  "tasks_sha256": "1fd72f71eaf8170b45782beede0d91544e1f7142e98c0642560af814382f01ef",
+  "kin_fp": "2ebcbf17",
+  "act_scale": 1.0,
+  "metrics": {
+    "n": 512,
+    "n_ref": 512,
+    "success": 0.55078125,
+    "collision_free_success": 0.546875,
+    "time_ok_1p3": 0.361328125,
+    "collision_rate": 0.017578125,
+    "collision_steps_mean": 0.1015625,
+    "travel_ratio_median": 2.425084352493286,
+    "time_mean_s": 2.322056770324707,
+    "brakes_mean": 19.228515625,
+    "start_fail": 0.0,
+    "goal_ratio_2s": 0.25053170323371887,
+    "err_fail_med": 194.51763916015625,
+    "err_success_med": 0.1961677223443985,
+    "dls_share": 0.634765625,
+    "time_budget": "teacher×2(≥3 s)"
+  },
+  "simulation_wall_s": 488.4280448999925
+}