Pipeline controller: plan 2 (hard +, error +50 %), backlog throttle, 2 trajectory workers, stop rules, summaries every 50; budget reserve

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

tasks_gen/train/_logs/G1039.json

@@ -0,0 +1,16 @@
+{
+ "id": "G1039",
+ "pool": "train",
+ "object_type": "CLAS",
+ "category": "H",
+ "attempts": [
+  {
+   "stage": "validate",
+   "oracle": 100,
+   "null": 30
+  }
+ ],
+ "accepted": true,
+ "error_kind": null,
+ "spent_total": 72.9203
+}