documentation updates

docs/reference/API-routes.md

@@ -277,6 +277,8 @@ Both fields are optional. Only provided fields are updated.
 | GET | /episodes/search?q=&limit= | FTS keyword search across all episodes |
 | GET | /episodes/:id | Get episode by ID |
 | GET | /sessions/:id/episodes?limit=&offset= | Paginated episodes for a session |
+| GET | /sessions/:id/episode-stats | Aggregate: count, total tokens, max id (summarization threshold check) |
+| GET | /sessions/:id/episodes/since/:afterId | Episodes newer than :afterId, chronological (un-summarized tail) |
 | DELETE | /episodes/:id | Delete episode (SQLite + Qdrant cleanup) |
 
 > Route ordering: `/episodes/search` must be defined before `/episodes/:id`.