fix: harden DGR-017 contract continuity

.scratch/distributed-gguf-runtime/evidence/DGR-017/README.md

@@ -161,13 +161,13 @@ seeing a result. Each of those moves now has a test that names it:
 - admit the dense fallback → `test_admitting_the_dense_attention_fallback_after_the_fact_is_rejected`
 - shrink the reserve → `test_relaxing_the_per_node_reserve_after_the_fact_is_rejected`
 
-**Be precise about what the seal does.** `contract_sha256` is tamper-*evidence*, not
-tamper-proofing. Nothing checked into a repo can stop an agent that rewrites the
-threshold *and* re-seals the digest — `test_resealing_a_mutated_contract_changes_its_digest`
-asserts that path openly. What the seal removes is the *silent* mutation: the digest
-moves, and the change becomes a visible diff on a file whose entire purpose is to not
-change, still claiming `contract_id: glm-5.2-max-alpha/v1`. Reviewers, not hashes, are
-the enforcement; the hash makes sure there is something to review.
+**Contract continuity is fail-closed.** The document’s `contract_sha256` detects
+accidental edits, and the approved v1 digest is pinned independently in code. A caller
+that changes a threshold and re-seals it under `glm-5.2-max-alpha/v1` is rejected by
+`test_resealing_a_mutated_v1_contract_is_rejected`; amendments require a new supported
+contract identity under human review. Parsed nested state is recursively immutable,
+so thresholds cannot change between validation and use; `to_dict()` returns an isolated
+copy rather than exposing the validated object.
 
 ## 6. Upstream status — the gating risk for DGR-004/DGR-018
 

.scratch/distributed-gguf-runtime/evidence/DGR-017/commands.txt

@@ -98,3 +98,18 @@ $VP -m pytest -q tests/test_tracker_routing.py::test_tracker_dashboard_can_cance
   -> 1 passed, repeated 5/5 in isolation
 $VP -m pytest -q            # integrated rerun
   -> 852 passed, 13 skipped in 253.30s (0:04:13)
+
+# ---------------------------------------------------------------------------
+# 7. Late independent-review repair (2026-07-14)
+# ---------------------------------------------------------------------------
+PYTHONPATH=packages/node $VP -m pytest -q tests/test_glm_alpha_target.py
+  -> 99 passed in 0.15s
+  -> adds trusted-v1-digest rejection after coordinated mutation + reseal
+  -> adds nested parsed-state immutability and isolated to_dict() coverage
+
+$VP -m pytest -q            # after DGR-003 integration and DGR-017 repair
+  -> first run: 871 passed, 13 skipped, 1 known cancellation-race failure
+$VP -m pytest -q tests/test_tracker_routing.py::test_tracker_dashboard_can_cancel_inflight_proxy
+  -> 5/5 passed in isolation
+$VP -m pytest -q            # integrated rerun
+  -> 872 passed, 13 skipped in 253.46s (0:04:13)