Keep outlet snapshots and contact details out of browser persistence

[sridharkalaibala]

Outlet windows now keep their billing snapshot in memory instead of writing the complete snapshot to sessionStorage. Existing persisted snapshots are removed on opening. Shop phone details use a volatile store, removing the new clear-text persistence paths identified by code scanning.

Minimize/restore still preserves the existing window and cart. Reloaded windows revalidate register state through the API. Regression checks verify per-window isolation and that shop phone details are absent from browser storage.

Validation: 64 outlet/register/translation tests and 11 settings tests passed; attribution check passed. Full desktop verification is running.

[github-actions]

Merged to develop. Anyone can test this - you do not need write access.

Try it at https://develop.posnic.io, or run it yourself:

git fetch origin develop && git checkout develop
npm install && npm --prefix api install
npm run dev   # then http://localhost:3000

When you have tested it, say what you did and what happened, and set
QA passed or QA failed. If you cannot set labels, just comment -
a maintainer will.

Reporting that something is broken is as useful as fixing it. It is
better found here than by a shopkeeper.