Since the initial key backup can take several minutes for some users, this moves
the upload step to the background. The create key backup flow now only marks
all sessions for backup synchronously, with the actual backup happening later.
The key backup panel in Settings gains a new row to show a summary of upload
status. Users are directed there if they wish to know if the backup is done.
The text in various related dialogs has also been tweaked to fit the new flow.
Including unused substitutions triggers console logs, so change the key backup
panel to only substitute what's actually used in each message.
Fixes https://github.com/vector-im/riot-web/issues/8047.
Adds a New Recovery Method dialog which is shown when key backup fails because
of a version mismatch / version not found error.
The set up button in the dialog currently only marks a device as verified (via a
verification prompt) instead of the eventual restore and cross-sign flow, since
those pieces don't exist yet.
Signed-off-by: J. Ryan Stinnett <jryans@gmail.com>
Continues from Matthew's work: adds a feature flag & panel in
user settings to create a backup.
Can't restore a backup yet, nor even continue backing up to the same
backup after a refresh.
