fix(portals): preserve playlist ownership during detail handoffs

docs/architecture/portal-detail-navigation.md

@@ -270,6 +270,22 @@ handler as the header Back.
 - Do not force both portals into the same browse/detail behavior unless the full
   portal detail architecture is being changed.
 
+### Arrival and asynchronous ownership
+
+The shared catalog view initializes the category and consumes its Stalker
+handoff together, after the facade's optional `routeReady` signal allows it.
+Stalker exposes the route session's readiness, withheld from NavigationStart
+until the destination playlist and section are installed. Cancelled navigation
+reconciles the current route. Reused category routes also reinitialize when
+their playlist changes; readiness changes alone must not close an open detail
+on query-only navigation.
+
+Collection detail wrappers invalidate pending playlist loads before restoring
+their store snapshot on destruction. Route sessions must compare the actual
+store owner with the route, rather than trusting only their last initialized
+playlist id. Xtream playlist reads likewise discard completions superseded by
+a selection, metadata update, reset or newer read.
+
 ## Xtream
 
 Xtream category and search details are represented by canonical routes.

docs/architecture/stalker-portal.md

@@ -393,6 +393,14 @@ Internal structure to preserve:
   `isCategoryResourceFailed()` / `isPaginatedContentFailed()` for explicit
   error handling.
 
+Category arrays belong to `categoryPlaylistKey`, not just the content type.
+Every category reader checks that owner; a portal switch clears all four
+section caches before loading the destination. Aborted or foreign-portal
+responses (including errors and radio fallbacks) cannot write into the active
+cache. Explicit category resets reload even when the playlist object remains
+unchanged. This contract applies to collection details as well as routed
+catalogs, because both use the root Stalker store.
+
 Failure-handling rule:
 
 - Failed category or content requests must degrade into empty/error UI state,