Keep command output to the README's stdout and stderr rules (closes #224)

The startup banner moves from stdout to stderr, so a `completion`
script, a `config get` value and the hidden `__complete` command print
only their own output. `--quiet`, `--cron` and `--json` still suppress
it.

A failing `remote info`, `prune` or `snapshot remove` under `--json`
now reports its error on stderr. Their reporters returned early under
`--json`, so the failure reached neither stream.

`snapshot verify --quiet` writes no report. A failure is still
returned and printed on stderr, with the same exit status.

Judgement call: the banner's stream, posted on the issue for the owner.

Model: opus-5-5

TODO.md

@@ -31,6 +31,14 @@ the tag exists and is exercised; what is left is merging `next` to
   `snapshot verify --quiet` printed its whole report; it now prints
   none, and a failure still reaches stderr with the same exit status.
 
+- 2026-10-06: Made a backup without `--cron` of a snapshot with two or
+  more `paths` complete instead of panicking with `close of closed
+  channel` ([issue #253](https://git.eeqj.de/sneak/vaultik/issues/253)).
+  `Scan` runs once per path and started and stopped the progress
+  reporter each time, and a second stop panics. The reporter is now
+  started and stopped once per snapshot, around the scans of all its
+  paths.
+
 - 2026-10-06: Made a restore path argument select only that path and
   what is beneath it
   ([issue #223](https://git.eeqj.de/sneak/vaultik/issues/223)). The

internal/snapshot/scanner.go

@@ -224,12 +224,6 @@ func (s *Scanner) Scan(
 		log.Debug("No storage configured, blobs will not be uploaded")
 	}
 
-	// Start progress reporting if enabled
-	if s.progress != nil {
-		s.progress.Start()
-		defer s.progress.Stop()
-	}
-
 	// Phase 0: Repair any state left by an interrupted previous run, then
 	// load known files and chunks from the database into memory for fast
 	// lookup.
@@ -300,7 +294,9 @@ func (s *Scanner) Scan(
 	return result, nil
 }
 
-// GetProgress returns the progress reporter for this scanner
+// GetProgress returns the progress reporter for this scanner, or nil when
+// progress is off. Scan neither starts nor stops it: the caller does,
+// once for all the paths it scans, because a second Stop panics.
 func (s *Scanner) GetProgress() *ProgressReporter {
 	return s.progress
 }

internal/vaultik/snapshot.go

@@ -281,6 +281,11 @@ func (v *Vaultik) resolveSnapshotPaths(snapName string) ([]string, error) {
 func (v *Vaultik) scanAllDirectories(
 	scanner *snapshot.Scanner, resolvedDirs []string, snapshotID string,
 ) (*snapshotStats, error) {
+	if progress := scanner.GetProgress(); progress != nil {
+		progress.Start()
+		defer progress.Stop()
+	}
+
 	stats := &snapshotStats{}
 
 	for i, dir := range resolvedDirs {

internal/vaultik/two_path_snapshot_test.go

@@ -0,0 +1,71 @@
+package vaultik_test
+
+import (
+	"context"
+	"maps"
+	"path/filepath"
+	"testing"
+
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/vaultik/internal/config"
+	"sneak.berlin/go/vaultik/internal/database"
+	"sneak.berlin/go/vaultik/internal/log"
+	"sneak.berlin/go/vaultik/internal/storage"
+	"sneak.berlin/go/vaultik/internal/vaultik"
+)
+
+// A backup without --cron runs the progress reporter while one scanner
+// scans each path of the snapshot in turn. See
+// https://git.eeqj.de/sneak/vaultik/issues/253.
+//
+//nolint:paralleltest // installs the global logger via log.Initialize
+func TestBackupWithoutCronOfTwoPathSnapshotRestoresBothPaths(t *testing.T) {
+	log.Initialize(log.Config{})
+
+	const snapshotName = "data"
+
+	fs := afero.NewOsFs()
+	tempDir := t.TempDir()
+	firstDir := filepath.Join(tempDir, "first")
+	secondDir := filepath.Join(tempDir, "second")
+	storeDir := filepath.Join(tempDir, "remote")
+	restoreDir := filepath.Join(tempDir, "restored")
+	dbPath := filepath.Join(tempDir, "index.sqlite")
+
+	ctx := context.Background()
+	files := writeFaultSourceTree(t, fs, firstDir)
+	maps.Copy(files, writeFaultSourceTree(t, fs, secondDir))
+
+	cfg := faultTestConfig()
+	cfg.IndexPath = dbPath
+	cfg.ChunkSize = config.Size(faultChunkSize)
+	cfg.Snapshots = map[string]config.SnapshotConfig{
+		snapshotName: {Paths: []string{firstDir, secondDir}},
+	}
+
+	store, err := storage.NewFileStorer(storeDir)
+	require.NoError(t, err)
+
+	db, err := database.New(ctx, dbPath)
+	require.NoError(t, err)
+
+	repos := database.NewRepositories(db)
+	v := newBackupVaultik(ctx, cfg, store, repos, db, fs)
+
+	require.NoError(t, v.CreateSnapshot(&vaultik.SnapshotCreateOptions{
+		Snapshots: []string{snapshotName},
+	}))
+
+	id := localSnapshotID(ctx, t, repos, snapshotName)
+	require.NoError(t, db.Close())
+
+	reader := newReaderVaultik(ctx, cfg, store, nil, fs)
+	require.NoError(t, reader.Restore(&vaultik.RestoreOptions{
+		SnapshotID: id,
+		TargetDir:  restoreDir,
+		Verify:     true,
+	}))
+
+	assertRestoredTree(t, fs, restoreDir, files)
+}