[SS-54] Add dialog to allow local deletion if network deletion fails

[AL-Session]

Contributor checklist

• I have tested my contribution on these devices:

• Virtual Pixel 3a, Android 9 API 28
• Virtual Pixel 3a, Android 14 API 34

• My contribution is fully baked and ready to be merged as is
• I ensure that all the open issues my contribution fixes are mentioned in the commit message of my first commit using the Fixes #1234 syntax

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Description

New functionality: If the user goes to Settings > Clear Data and chooses to "Clear device and network", then should the network data deletion fail the user is informed of this issue and asked if they would like to delete local device data only instead. If they proceed then local device data is deleted as if that had been their first choice.

One way to quickly test this functionality & see this new modal dialog is to:

• Get to the point where you can "Clear device and network", and then
• Drag down from the top of the screen to show the Android settings and turn Flight Mode on, then
• Click the current modal's "Clear" button.

As we're in flight mode, a short while after we attempt to perform the network deletion it will fail and the new modal displaying "An unknown error occurred and your data was not deleted. Do you want to delete your data from just this device instead? [Clear Device] [Cancel]". At this point the [Clear Device] button will do just that, while the [Cancel] button will cancel out of the operation.

[AL-Session]

Reversion of dev merge & libsession-util addition has been undone following dev process meeting.

[bemusementpark]

looks good!