Add accepted chunk map contract

docs/roadmap/future.md

@@ -18,20 +18,10 @@ not as committed release dates.
 
 ### Export Accepted Chunk Maps
 
-- Add an option to emit the accepted materialized chunk map as a proper,
-  framework-owned artifact with a documented schema identity, version, media
-  type, canonical encoding, and source/chunker provenance.
-- Export the exact ordered chunks used for lane execution, including stable
-  chunk IDs and current-source ranges. Do not expose a model's raw boundary
-  proposal or require a second model call to reconstruct information already
-  owned by the framework.
-- Treat chunk-map export as an output concern rather than an ordinary
-  extraction lane. Chunking is pipeline-wide and precedes lane extraction; a
-  pseudo-extractor would duplicate work and obscure that ownership boundary.
-- Keep the generic contract independent of D&D interpretation. Namespaced
-  annotations may be preserved when they are part of the accepted chunk plan,
-  but downstream applications should not need domain-specific annotations to
-  understand chunk identity, order, or source coverage.
+Add an opt-in, framework-owned durable artifact for the exact accepted
+materialized chunks used by lane execution. The accepted contract, output
+boundary, provenance policy, and exclusions are defined in
+[Accepted Chunk Map Export](accepted-chunk-map-export.md).
 
 ### Extract D&D Scene Descriptions