Display limits of email recovery

[florentos17]

tackling the issue 3219 (duplicated with the issue 3274)

[florentos17]

This curious thing is happening: when accessing the recover deleted messages panel, at first an error is thrown, but when i trigger a hot reload, then everything is fine:

IMG_0450.mov

the method is this:

String getRestorationHorizon(BuildContext context) {
    return ((_session
        ?.props[0] as Map<CapabilityIdentifier, CapabilityProperties>?)
        ?[capabilityDeletedMessagesVault]
        ?.props[0] as Map<String, dynamic>) // line causing the error
        ['restorationHorizon'];
  }

and the error is Type 'Null' is not a subtype of type 'Map<String, dynamic>' in type cast

[github-actions]

This PR has been deployed to https://linagora.github.io/tmail-flutter/3281.

[florentos17]

the issue i had the other day is now resolved, everything is working fine ! it looks like this

in the web version, the options in the dropdown are filtered out so that "30 days" and more do not show if the horizon is 15 days for example. but in the mobile version, the period is selected with this widget (same as the one we get by clicking the little calendar icon in the web version) and i did not want to change the suggested options because the widget is also used for other features.