feat: git-like project versioning (v1)

Linear per-project history per notes/project-versioning.md: named
checkpoints (thumbnail via renderer.captureFrame) plus auto-checkpoints
on save (60s throttle, ring of 20, named never rotate). Restore writes a
safety checkpoint first, then swaps the document outside undo/redo.
Media assets referenced by any version are pinned against deletion.
Migration v31-v32 stamps the schema; the version store lives in its own
IDB database with an in-memory fallback for tests. Versions popover in
the editor header for jump/rename/delete. 12 new tests.

1 files changed, 23 insertions, 0 deletions

diff --git a/apps/web/src/versions/versions-store.ts b/apps/web/src/versions/versions-store.ts
new file mode 100644
index 00000000..7ae957fb
--- /dev/null
+++ b/apps/web/src/versions/versions-store.ts
@@ -0,0 +1,23 @@
+import { create } from "zustand";
+
+/**
+ * UI-only state for the versions surfaces (popover + checkpoint dialog).
+ * Document state lives in EditorCore's VersionsManager — never here.
+ */
+interface VersionsState {
+	isPanelOpen: boolean;
+	isCheckpointDialogOpen: boolean;
+	setPanelOpen: (args: { open: boolean }) => void;
+	togglePanel: () => void;
+	openCheckpointDialog: () => void;
+	closeCheckpointDialog: () => void;
+}
+
+export const useVersionsStore = create<VersionsState>()((set) => ({
+	isPanelOpen: false,
+	isCheckpointDialogOpen: false,
+	setPanelOpen: ({ open }) => set({ isPanelOpen: open }),
+	togglePanel: () => set((state) => ({ isPanelOpen: !state.isPanelOpen })),
+	openCheckpointDialog: () => set({ isCheckpointDialogOpen: true }),
+	closeCheckpointDialog: () => set({ isCheckpointDialogOpen: false }),
+}));