Add 3-Day Outlook generation

docs/internal/state.md

@@ -5,7 +5,7 @@ This document describes the implemented filesystem state boundary.
 ## Purpose
 
 `internal/state` owns durable artifact paths, atomic JSON writes, metadata, and
-prior Daily snapshot lookup.
+prior comparable snapshot lookup.
 
 ## Inputs and Outputs
 
@@ -25,8 +25,8 @@ Outputs:
 - render preflight JSON
 - Markdown report path
 - metadata JSON
-- prior Daily snapshot metadata when available
-- prior Daily briefing package when loaded by path
+- prior comparable snapshot metadata when available
+- prior briefing package when loaded by path
 
 ## Boundaries
 
@@ -48,12 +48,13 @@ Workspace subdirectories must be relative paths that stay under
 ## State Behavior
 
 Managed artifact names use RunID, which is generated from report generation time
-and report ID. Daily metadata is stored beside Daily briefing snapshots by valid
-local date. Prior Daily snapshot lookup reads metadata for the same valid local
-date and returns the latest earlier compatible Daily Today or Daily Tomorrow
-run. The store can load a briefing snapshot by path for structured comparison.
-The store prepares the managed Markdown report path before `scriptorium run`
-writes it.
+and report ID. Metadata is stored beside briefing snapshots by report group and
+valid local date. Prior snapshot lookup reads metadata for the same valid local
+date and returns the latest earlier compatible run. Daily Today and Daily
+Tomorrow are compatible with each other; 3-Day Outlook is compatible with prior
+3-Day Outlook snapshots. The store can load a briefing snapshot by path for
+structured comparison. The store prepares the managed Markdown report path
+before `scriptorium run` writes it.
 
 ## Failure Behavior