feat: add settlement contract boundary

.scratch/distributed-inference-network/prd.json

@@ -145,11 +145,12 @@
         "Commit only this story's code changes with a focused conventional commit message"
       ],
       "priority": 6,
-      "passes": false,
+      "passes": true,
       "notes": "Source issue: .scratch/distributed-inference-network/issues/06-solana-stake-and-settlement.md",
       "dependsOn": [
         "US-003"
-      ]
+      ],
+      "completionNotes": "Completed by fresh Ralph/Codex session c257ffde with controller patches for clarified economics; verified by pytest, compileall, and diff check."
     },
     {
       "id": "US-007",
@@ -258,4 +259,4 @@
   "metadata": {
     "updatedAt": "2026-06-28T22:37:54.858Z"
   }
-}
+}