fix: close dashboard context panels on route exit

[KenkoGeek]

Summary

Close any open resource context panels when the FleetOps dashboard route is exited so a place details panel does not remain visible after navigating to Places.

The cleanup is attached to Ember's Route#deactivate hook, which only runs when the route is fully exited, rather than reacting to every route change.

Fixes fleetbase/fleetbase#458

Testing

• Added a regression test for operations/orders/index route teardown
• pnpm lint
• pnpm build
• pnpm exec ember test --test-port 0 --module "Unit | Route | operations/orders/index" --reporter tap

References

• Ember Route lifecycle: https://api.emberjs.com/ember/release/classes/route/methods/deactivate?anchor=deactivate
• Uses the existing resource-context-panel.closeAll() API from @fleetbase/ember-ui