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models/qualification.js

@@ -28,8 +28,8 @@ const qualificationSchema = new mongoose.Schema({
   // PhD fields — presence of topic_name signals PhD view on frontend
   topic_name:       { type: String, trim: true },
   topic_short_desc: { type: String, trim: true },
-  // Document image
-  degree_image: { type: String }
+  // Document images (array of filenames)
+  degree_image: { type: [String], default: [] }
 }, { timestamps: true });
 
 module.exports = mongoose.model('Qualification', qualificationSchema);