CarPlay app lacks error handling during poor internet connectivity situations

**iOS device model, version and app version**

Model Name: iPhone 17 Pro / Wireless CarPlay
Software Version: iOS 27 beta
App version: latest Testflight

**Home Assistant Core Version**

2026.7.2

**Describe the bug**
CarPlay app does not appear to have as much error handling as the main app when there is very weak cell reception or no internet connection.

### Areas Tab
It shows areas here but you cannot tap through to any of the areas.

When it's working normally you get the brief "loading" message followed by your entities loading in. When it can't be loaded due to poor connectivity it never gets that far, never moves from this screen, it just makes it seem like your tap didn't register at all.

### Control Tab
This tab has an error message but "No domains available" is kinda misleading error text. It should say that it could not connect to Home Assistant and to check your connection or something like that.

I forgot to take screenshot of the Quick Access tab, the actions had generic icons though (`mdi:bookmark` I think) and no error message. I would assume it probably has same issue as Areas tab where you could tap it but it wouldn't do anything.

**To Reproduce**
Test when in a dead zone area with weak cell signal, or no internet. i didn't try this but could maybe put iPhone into airplane mode or something.

**Expected behavior**
The main iPhone app handles these situations by saying you're disconnected and to check your connection. CarPlay app should have something along these lines too imo.

**Screenshots**

**Additional context**

Start with the CarPlay Areas, Control, and Quick Access tab entry points and reproduce the issue with weak connectivity or Airplane Mode. Compare the CarPlay behavior with the main iPhone app's disconnected state, then verify that failed loading shows a connection-related message and does not leave taps or generic icons without feedback.

Written by the indexing model from the issue text.