feat(ui): prominent banner for wrong-key errors at login/sync (#3475)

The wrong-key error was a long unwrapped sentence buried under
"Successfully authenticated.", and wrapped by eyre error formatting

add

- print_error(title, description) — red box-drawn bars across the
terminal width (capped at 100 cols) with bold title; word-wraps the
description; plain "Error:" header when stderr isn't a TTY.
- format_sync_error(SyncError) -> eyre::Report — intercepts WrongKey to
print the banner and exit(1) so eyre's footer never runs; forwards other
variants unchanged.

Use it from:
  - account/login.rs — replaces bail\! in the wrong-key path
  - command/client/sync.rs — .map_err(format_sync_error)? on sync()
  - store/push.rs and store/pull.rs — .map_err on check_encryption_key


## Checks
- [ ] I am happy for maintainers to push small adjustments to this PR,
to speed up the review cycle
- [ ] I have checked that there are no existing pull requests for the
same thing

0 files changed, 0 insertions, 0 deletions