Two output-style fixes plus a quiet-mode correction.
Banner: a manual scan of os.Args in CLIEntry decides whether to suppress
the banner (--quiet/-q/--cron), then prints it before cobra parses any
arguments. This makes the banner appear even when cobra rejects bad args
("requires at least 2 arg(s)") and on --help — paths that previously
skipped PersistentPreRun entirely. The cobra-side hook plumbing (sync.Once,
PersistentPreRun, custom HelpFunc) is removed.
Errors: rootCmd.SilenceErrors = true so cobra no longer prints its own
"Error: <msg>" line. Any error returned from Execute() goes through
ui.New(os.Stderr).Error(...), giving the documented "🛑 ERROR: <msg>"
format. A new helper cli.ReportError() formats errors from goroutine
paths that can't return through cobra's normal return chain; every
CLI command's fx-goroutine error path now calls it alongside the
existing structured log.Error so both channels record the failure.
Quiet mode: previously --quiet/--cron swapped Vaultik.UI to io.Discard,
which silenced Warning and Error messages too — contradicting the
documented "suppresses non-error output" semantics. ui.Writer now has
a SetQuiet flag that drops Begin/Complete/Info/Notice/Detail/Progress/
Banner only; Warning and Error always emit.
Also folds in restore.go cleanups the audit flagged: the hardcoded
"WARNING:" prefix on the failed-files block now uses ui.Warning +
ui.Detail, the post-restore "Restored N files" line uses ui.Complete,
and the "No files found to restore" branch emits both log.Warn and
ui.Warning so structured logs continue to capture it under --verbose.
Renames the top-level `restore` command to `vaultik snapshot restore`
for consistency with `vaultik snapshot create`. The factory follows the
sibling pattern (newSnapshotRestoreCommand) and its file is renamed to
snapshot_restore.go to match.
