final polishing

docs/openapi.yaml

@@ -390,6 +390,10 @@ paths:
               schema:
                 type: string
                 format: binary
+        '404':
+          description: Not Found or Unauthorized
+        '400':
+          description: Bad Request - Id not a positive integer
 
   /api/materials:
     get:

src/controllers/projectsController.js

@@ -110,7 +110,7 @@ export async function deleteProjectFileHandler(req, res) {
       return res.status(404).json({ error: 'File not found or unauthorized' });
     }
 
-    res.status(200).json({ message: 'File deleted successfully' });
+    res.status(204).json({ message: 'File deleted successfully' });
   } catch (error) {
     res.status(400).json({ error: 'Invalid file ID' });
   }