Add project revision foundation

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

@@ -354,14 +354,31 @@ Persist project-wide change history and restore points across reloads and applic
 
 Tasks:
 
-- add project-scoped monotonic revisions
-- record immutable server-side change sets with before/after state
-- add optimistic revision checks for stale commands
+- [x] add project-scoped monotonic revision storage
+- [x] add immutable append-only server-side change-set storage with versioned
+  forward/inverse payloads
+- [x] add optimistic checks when appending a revision
+- route domain writes and history records through one shared transaction
+- model serializable domain command descriptions outside React
 - 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
 
+Implemented foundation:
+
+- projects start at revision zero and advance monotonically
+- each revision has one separately stored logical change set
+- revision metadata, change-set payloads and the project counter are committed
+  in one SQLite transaction
+- a stale expected revision produces no history writes
+- integration coverage verifies sequential revisions, stale-command rejection
+  and rollback after a forced late persistence failure
+
+The current editor operations are not connected to this history boundary yet.
+Undo/redo therefore remains session-local until the remaining tasks are
+implemented.
+
 Acceptance criteria:
 
 - undo/redo remains available after a page reload