more initial changes

internal/mover/mover.go

@@ -0,0 +1,19 @@
+package mover
+
+import (
+    "fmt"
+    "os"
+    "path/filepath"
+)
+
+// Move moves the file to destDir/destName, creating directories as needed.
+func Move(src, destDir, destName string) (string, error) {
+    if err := os.MkdirAll(destDir, 0o755); err != nil {
+        return "", fmt.Errorf("mkdir %s: %w", destDir, err)
+    }
+    destPath := filepath.Join(destDir, destName)
+    if err := os.Rename(src, destPath); err != nil {
+        return "", fmt.Errorf("rename %s -> %s: %w", src, destPath, err)
+    }
+    return destPath, nil
+}