Payroll period approval workflow and per-worker app status

This release introduces a structured, period-based approval process for payroll and gives admins clear visibility into each worker's mobile app and GPS status.

New

Payroll period approval: The payroll export tab is now a guided, period-first step flow — approve shifts, then gain period sign-off (with an approver checklist and a review-before-approve summary), then export. You can withdraw an approval when needed, and the whole timeline of approvals and related changes is visible in one place.
Approvers and notifications: Set which people must sign off on a payroll period and who gets notified, right from Settings → Salary. When a period is fully approved, recipients receive an email and in-app notification (in English, Danish and Swedish).
Automatic re-approval on changes: If a shift, sick leave or approved piecework inside an already signed-off period is changed, sign-offs are cleared, the period is flagged as needing re-approval, and approvers are notified — so payroll always reflects the latest data.
Per-worker app status: The Employees list now shows each worker's installed app version, flags when a build is behind the latest store release, and indicates at a glance whether GPS is working (with a tooltip explaining any blocker such as location services being off or a denied background permission).
Mobile app details in the employee profile: Each employee's profile now includes a Mobile app card showing app version versus the newest available, platform and OS, location-service state, foreground and background permissions, precise-vs-approximate location, and when it was last reported.

Improved

Stale-period warnings guard against exporting a payroll period that hasn't been approved or has changed since approval, and a status chip on the Shift Approval tab shows where each period stands.

Fixed

Absence export dates now use your organization's timezone, so leave registered around midnight no longer lands on the wrong day and the correct shifts are converted.