Add Verbose log level between Info and Debug

Implemented full log level hierarchy: Fatal, Error, Warn, Info, Verbose, Debug.
- Verbose level (-v) shows detailed operations like file changes (M/A/D)
- Debug level (-vv) shows low-level tracing with caller info
- Quiet mode (-q) sets level to Error, suppressing Info messages
- Banner and summary output now use log levels for filtering

internal/cli/gen.go

@@ -115,11 +115,9 @@ func (mfa *CLIApp) generateManifestOperation(ctx *cli.Context) error {
 		return fmt.Errorf("failed to generate manifest: %w", err)
 	}
 
-	if !ctx.Bool("quiet") {
-		elapsed := time.Since(mfa.startupTime).Seconds()
-		rate := float64(s.TotalBytes()) / elapsed / 1e6
-		log.Infof("wrote %d files (%.1f MB) to %s in %.1fs (%.1f MB/s)", s.FileCount(), float64(s.TotalBytes())/1e6, outputPath, elapsed, rate)
-	}
+	elapsed := time.Since(mfa.startupTime).Seconds()
+	rate := float64(s.TotalBytes()) / elapsed / 1e6
+	log.Infof("wrote %d files (%.1f MB) to %s in %.1fs (%.1f MB/s)", s.FileCount(), float64(s.TotalBytes())/1e6, outputPath, elapsed, rate)
 
 	return nil
 }