fix(firstleg): allow audited carrier node time corrections

firstleg/src/main/resources/openapi/carrier-schedule-query-v1.yaml

@@ -82,7 +82,9 @@ paths:
             schema: {$ref: '#/components/schemas/ManualNodeRequest'}
       responses:
         '200':
-          description: Idempotent fact append; only actualAt advances and actual EMPTY_RETURNED stops
+          description: Idempotent fact append; estimated facts never advance actual progress; the current latestActualNode may append an audited correction fact and replace latestActualAt; a later actual node advances progress and actual EMPTY_RETURNED stops
+        '409':
+          description: A0409 when expectedVersion is stale or a manual actual node is earlier than latestActualNode
           content: {application/json: {schema: {$ref: '#/components/schemas/DetailEnvelope'}}}
 components:
   parameters:
@@ -122,7 +124,7 @@ components:
     ManualNodeRequest:
       type: object
       required: [expectedVersion, standardNode, observedAt, reason]
-      description: estimatedAt and actualAt cannot both be null; estimatedAt never advances the latest actual node.
+      description: estimatedAt and actualAt cannot both be null; estimatedAt never advances the latest actual node; when actualAt is present, standardNode may equal latestActualNode to correct latestActualAt through a new immutable audit fact, but cannot be earlier.
       properties:
         expectedVersion: {type: integer, minimum: 0}
         standardNode: {$ref: '#/components/schemas/StandardNode'}