Document resilient reports and remove obsolete warning material

docs/policy/architecture.md

@@ -2,7 +2,7 @@
 
 **Base Policy Version:** 1.0
 
-**Last Updated**: 2026-09-23
+**Last Updated**: 2026-09-24
 
 ## Purpose and System Shape
 
@@ -48,7 +48,9 @@ hidden global state.
 - Keep LLM concurrency bounded and context-aware through PromptKit's engine-local
   per-backend admission. Proposal and validation calls selecting the same backend
   share that capacity, including retries and repairs. Preserve deterministic
-  collection order and cancellation of remaining work on runtime failure.
+  collection order. Recoverable model-operation failures stay local to their
+  proposal response or validation batch; fatal invariant/application failure
+  and parent cancellation stop peers and join them.
 - Keep module and validator identities, reason codes, and execution-class
   distinctions stable where exposed as contracts.
 
@@ -61,12 +63,14 @@ describe how these requirements are implemented.
 Keep transcript mutation and output handling deterministic around external
 calls. Reports and correction ledgers are derived from processing results.
 Preserve the separation between transient processing state and filesystem
-adapters; physical artifact placement and retention belong to
+adapters; physical report placement and optional debug retention belong to
 [operations](../operations.md).
 
 Public CLI, configuration, output-schema, diagnostics, report, prompt, module,
 and validator contracts should remain stable unless a change is deliberate and
-tested. Prefer additive, compatible report changes. Current implementation
+tested. The resilience work intentionally replaced the earlier JSON process
+report with versioned errors/recoveries YAML and a fixed Markdown overview;
+future changes should treat those current contracts deliberately. Current implementation
 limits are documented in the [internal overview](../internal/overview.md#current-scope);
 they are not additional prohibitions on future development.