[rashidazarang]

What

Both persistence-failure tests in src/store.test.ts fail on a clean checkout:

× keeps editing available when a confirmed transaction cannot persist
  → expected 'saved' to be 'error'
× persists normalized documents and handles write/read failures
  → expected true to be false

Why

The tests replaced localStorage.setItem by direct assignment. jsdom's Storage is an exotic object: assigning to a property stores it as an item instead of overriding the method, so the throwing stub never ran — the store saved successfully and the assertions comparing against the failure path broke.

How

Stub with vi.spyOn(Storage.prototype, "setItem" / "getItem") instead, which intercepts the method regardless of how the environment implements the instance, and mockRestore() afterwards so later assertions in the same test see real storage. No production code touched.

Verify

npm test   # 31 passed + 7 companion passed (was: 2 failed)