Add persistent history stacks

docs/spec/07-implementation-phases-todo.md

@@ -361,7 +361,7 @@ Tasks:
 - route domain writes and history records through one shared transaction
 - define concrete serializable domain command descriptions and executors
   outside React
-- persist undo/redo eligibility on the server
+- [x] persist undo/redo eligibility on the server
 - add named and periodic logical project snapshots
 - restore a historical snapshot as a new revision
 - keep database backups separate from logical history
@@ -379,6 +379,12 @@ Implemented foundation:
 - an internal typed `circuit-device-row.update` command uses the same boundary,
   records derived ProjectDevice override metadata and rejects cross-project
   rows, device links and rooms
+- relational project-wide undo/redo stacks persist eligible original change
+  sets, enforce LIFO order and clear redo on a new user command
+- stack transitions are part of the domain/revision transaction and have
+  late-failure rollback coverage
+- a read-only project history endpoint exposes revision, stack depths and top
+  change-set ids
 - revision metadata, change-set payloads and the project counter are committed
   in one SQLite transaction
 - a stale expected revision produces no history writes