Fix misleading download dialog

[Almost-Senseless-Coder]

If a user declines to download the language model English (US), they will start seeing misleading download dialogs when they launch the app.

This is caused by the following mechanism:

• The app starts up with the language being set to English (United States) - the default.
• Next, the app checks for model availability.
• The model isn't available and the download dialog gets shown.
• At this point, the app is done fetching the stored language value from persistent storage and swaps out the language name mentioned in the dialog.

The result is that the user may think their preferred language didn't get installed yet, even though it did.