Add direct WP-0024 load driver handoff

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a02669-87ee-7a31-b111-edc95a16e0fa

interfaces/RAILIANCE-WP-0024-T02-synthetic-load-driver.json

@@ -0,0 +1,97 @@
+{
+  "interface": "railiance.synthetic-load-driver",
+  "version": 1,
+  "workplan_id": "RAILIANCE-WP-0024",
+  "task_id": "RAILIANCE-WP-0024-T02",
+  "contract_id": "RAILIANCE-WP-0024-T02-SYNTHETIC-01",
+  "owner": "audit-core",
+  "invocation": [
+    "<driver>",
+    "<phase>",
+    "--contract-id",
+    "RAILIANCE-WP-0024-T02-SYNTHETIC-01"
+  ],
+  "stdout": "Exactly one JSON object containing exactly the keys declared for the phase.",
+  "stderr": "Must not contain a bearer, payload, response body, database credential, Secret data or OpenBao output.",
+  "phases": {
+    "baseline": {
+      "keys": [
+        "contract_id",
+        "fixture_id",
+        "status",
+        "secret_values_observed"
+      ],
+      "status": [
+        "ready"
+      ]
+    },
+    "expect-unavailable": {
+      "keys": [
+        "contract_id",
+        "fixture_id",
+        "status",
+        "http_status",
+        "attempts",
+        "secret_values_observed"
+      ],
+      "status": [
+        "retryable_unavailable"
+      ],
+      "http_status": [
+        503
+      ],
+      "minimum_attempts": 1
+    },
+    "expect-recovered": {
+      "keys": [
+        "contract_id",
+        "fixture_id",
+        "status",
+        "http_status",
+        "attempts",
+        "secret_values_observed"
+      ],
+      "status": [
+        "accepted",
+        "duplicate"
+      ],
+      "http_status": [
+        200,
+        202
+      ],
+      "minimum_attempts": 1
+    },
+    "cleanup": {
+      "keys": [
+        "contract_id",
+        "fixture_id",
+        "status",
+        "secret_values_observed"
+      ],
+      "status": [
+        "clean"
+      ]
+    }
+  },
+  "invariants": [
+    "contract_id equals the requested contract on every phase",
+    "fixture_id is identical across every phase",
+    "secret_values_observed is false on every phase",
+    "only a separately approved synthetic sender and tenant are used",
+    "the bearer is read only from an approved mounted file and never reaches the parent shell",
+    "expect-unavailable treats HTTP 503 as retryable evidence and never retries 400, 401, 403 or 409",
+    "cleanup stops and removes driver-owned ephemeral runtime; an accepted immutable audit fixture is retained under the audit evidence contract",
+    "temporary sender identity cleanup remains an attended railiance-platform custody action"
+  ],
+  "candidate_receipt": {
+    "source_repo": "audit-core",
+    "required_fields": [
+      "source_revision",
+      "source_path",
+      "driver_revision",
+      "reviewer",
+      "created_at"
+    ],
+    "registration_executes_driver": false
+  }
+}