feat: switch upload hash to md5

backend/app/services/common.go

@@ -2,7 +2,7 @@ package services
 
 import (
 	"context"
-	"crypto/sha256"
+	"crypto/md5"
 	"encoding/hex"
 	"encoding/json"
 	"io"
@@ -196,7 +196,7 @@ func (s *common) CompleteUpload(ctx context.Context, userID int64, form *common_
 	}
 	defer dst.Close()
 
-	hasher := sha256.New()
+	hasher := md5.New()
 	var totalSize int64
 
 	for _, partNum := range parts {
@@ -346,7 +346,7 @@ func (s *common) Upload(
 	}
 
 	// Hash calculation while copying
-	hasher := sha256.New()
+	hasher := md5.New()
 	size, err := io.Copy(io.MultiWriter(dst, hasher), src)
 	dst.Close() // Close immediately to allow removal if needed
 	if err != nil {