Fix snapshot list to fail on manifest errors

- Remove error suppression for manifest decoding errors
- Manifest read/deserialize errors now fail immediately with clear error messages
- This ensures we catch format mismatches and other issues early

internal/cli/snapshot.go

@@ -548,8 +548,7 @@ func (app *SnapshotApp) List(ctx context.Context, jsonOutput bool) error {
 			// Try to download manifest to get size
 			totalSize, err := app.getManifestSize(ctx, snapshotID)
 			if err != nil {
-				log.Warn("Failed to get manifest size", "id", snapshotID, "error", err)
-				totalSize = 0
+				return fmt.Errorf("failed to get manifest size for %s: %w", snapshotID, err)
 			}
 
 			snapshots = append(snapshots, SnapshotInfo{