Restore named project snapshots

AGENTS.md

@@ -233,8 +233,10 @@ stored command payloads.
 Named logical snapshots can be created and listed through project-scoped API
 endpoints. Their schema-versioned payload contains the complete supported
 project runtime state and a SHA-256, excludes global/upgrade-only data and does
-not change the project revision or undo/redo stacks. Restore is not implemented
-yet.
+not change the project revision or undo/redo stacks. Restoring a server-stored
+snapshot verifies its checksum and the current-state hash, replaces supported
+project data atomically and records a new `restore` revision with a complete
+inverse command. Restore can therefore be undone and redone after a restart.
 Insertions and generated move targets use client-generated stable UUIDs, and
 undo restores the same ids from complete server snapshots. The tree response
 supplies the optimistic `currentRevision`; obsolete direct field PATCH,
@@ -298,7 +300,7 @@ Users must be able to override sizing suggestions.
 - Never edit an already applied migration.
 - Back up an existing database before applying a new migration.
 - Inspect generated SQL; it must contain only the intended schema change.
-- Keep database backups separate from future logical project snapshots.
+- Keep database backups separate from logical project snapshots.
 - Do not import the global SQLite singleton into domain services.
 - Keep synchronous SQLite transaction behavior inside persistence adapters.
 - Preserve stable UUIDs and explicit transaction boundaries for a later
@@ -306,7 +308,7 @@ Users must be able to override sizing suggestions.
 
 ## Current Deferred Work
 
-- snapshot restore, snapshot UI and periodic snapshot policy
+- snapshot UI and periodic snapshot policy
 - Revit/CSV/IFCGUID round-trip
 - full electrical sizing
 - multi-user/PostgreSQL operation