Plan sequence identity and combination implementation

docs/roadmap/sequences.md

@@ -1,9 +1,9 @@
 # Sequence Identity And Combination Roadmap
 
-Status: settled feature roadmap, ready for a staged implementation plan. This
-is the targeted end state, not an implemented contract. The subsequent plan will
-specify execution order, exact Go names and signatures, internal bookkeeping,
-and validation stages.
+Status: settled feature roadmap; implementation is specified in the
+[staged implementation plan](implementation.md). This document defines the
+targeted end state, not an implemented contract. The implementation plan owns
+execution order, exact Go names and signatures, bookkeeping, and validation.
 
 ## Purpose And Scope
 
@@ -906,8 +906,9 @@ policy ownership and inheritance transfer.
 
 ## Work Needed From The Baseline
 
-The implementation plan should cover these connected changes, with execution
-order and test sequencing defined there:
+The baseline needs the following connected capabilities to reach the target
+state. Execution order and test sequencing belong to the
+[implementation plan](implementation.md):
 
 - **Declarations and public API:** extend application registration to the settled
   identity model with one public registration type and definition field, an
@@ -993,6 +994,6 @@ status while preserving its decision content. The architecture policy is aligned
 Dynamic selectors extend the destinations covered by application registration;
 they retain the accepted application authority and final-validation boundary.
 
-No open feature decisions remain. The implementation plan should translate this
-end state into reviewable stages without adding guarantees, restrictions, or
+No open feature decisions remain. The implementation plan translates this end
+state into reviewable stages without adding guarantees, restrictions, or
 combination semantics.