Humanize file sizes in gen output, clean up temp on signal

- Humanize file sizes in verbose file listing (e.g., "76.8 MiB" not "76836984 bytes")
- Add signal handler to clean up temp file on Ctrl-C/SIGTERM during gen

internal/cli/gen.go

@@ -2,8 +2,11 @@ package cli
 
 import (
 	"fmt"
+	"os"
+	"os/signal"
 	"path/filepath"
 	"sync"
+	"syscall"
 	"time"
 
 	"github.com/dustin/go-humanize"
@@ -84,9 +87,24 @@ func (mfa *CLIApp) generateManifestOperation(ctx *cli.Context) error {
 		return fmt.Errorf("failed to create temp file: %w", err)
 	}
 
+	// Set up signal handler to clean up temp file on Ctrl-C
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		sig, ok := <-sigChan
+		if !ok || sig == nil {
+			return // Channel closed normally, not a signal
+		}
+		_ = outFile.Close()
+		_ = mfa.Fs.Remove(tmpPath)
+		os.Exit(1)
+	}()
+
 	// Clean up temp file on any error or interruption
 	success := false
 	defer func() {
+		signal.Stop(sigChan)
+		close(sigChan)
 		_ = outFile.Close()
 		if !success {
 			_ = mfa.Fs.Remove(tmpPath)

internal/scanner/scanner.go

@@ -10,6 +10,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/dustin/go-humanize"
 	"github.com/spf13/afero"
 	"sneak.berlin/go/mfer/internal/log"
 	"sneak.berlin/go/mfer/mfer"
@@ -354,7 +355,7 @@ func (s *Scanner) ToManifest(ctx context.Context, w io.Writer, progress chan<- S
 			return err
 		}
 
-		log.Verbosef("+ %s (%d bytes)", entry.Path, bytesRead)
+		log.Verbosef("+ %s (%s)", entry.Path, humanize.IBytes(uint64(bytesRead)))
 
 		scannedFiles++
 		scannedBytes += bytesRead