The mail module now supports marking certain data fields as read-only, helping prevent unintended changes to values that should stay fixed. This improves reliability in messaging features by making field behavior clearer and more controlled behind the scenes.

Fields can now be marqued as read only.
```
stringifiedDomain: attr({
    default: '[]',
    readonly: true,
}),
```

The contact display no longer includes leftover fax-related content, matching the current contact fields available in Odoo. This keeps the interface cleaner and avoids showing or maintaining an outdated communication option.

Fax field was removed somewhere between Odoo10 and 11. However there is still
some leftover about fax in contact widget. As there is no fax field anymore
and as it is easy to add it through inheritance let us remove it.

Closes #62105