Merge branch 'stack/agent-profiles-1-seam' into stack/agent-profiles-3-wire

# Conflicts:
#	docs/persistence-catalog.i18n.yaml
#	docs/persistence-catalog.md
#	docs/persistence-catalog.zh.md

docs/subsystems/session.md

@@ -171,7 +171,7 @@ interface EpochHeader {
 }
 ```
 
-Canonical form represents an empty system prompt or tool list as an absent field, matching how requests are built. Legacy v0 logs containing the removed `request/header-delta` event or its full-snapshot `fallback` reason are rejected at seed, append, and persistence-load boundaries rather than replayed incompletely.
+Canonical form represents an empty system prompt or tool list as an absent field, matching how requests are built. Legacy v0 logs containing the legacy `request/header-delta` event or its full-snapshot `fallback` reason are rejected at seed, append, and persistence-load boundaries rather than replayed incompletely.
 
 ### The route capacity event: `request/context`
 
@@ -266,7 +266,8 @@ type SurfaceEventType =
  *   (inclusive) through `end` (inclusive) with this node. Both must exist as
  *   surface nodes in the current surface. `start === end` replaces a single
  *   node. The node's {@link SessionEvent.sourceEventSeqs} must include every
- *   shadowed surface node. Used by compaction and possible other manipulations.
+ *   shadowed surface node. Used by compaction; any surface-replacing producer
+ *   may use it.
  */
 type SurfaceOp =
   | 'append'