Enhance gcode file schema to populate part information from partSku

- Added logic in the pre-validation hook to populate the `part` field in `parts` array based on the `partSku` if it is not already set.
- Improved data integrity by ensuring that part information is correctly retrieved and assigned during validation.

src/database/schemas/production/gcodefile.schema.js

@@ -28,6 +28,14 @@ gcodeFileSchema.pre('validate', async function () {
     const sku = await mongoose.model('filamentSku').findById(this.filamentSku).select('filament').lean();
     if (sku?.filament) this.filament = sku.filament;
   }
+  if (this.parts?.length) {
+    for (const partItem of this.parts) {
+      if (!partItem.part && partItem.partSku) {
+        const sku = await mongoose.model('partSku').findById(partItem.partSku).select('part').lean();
+        if (sku?.part) partItem.part = sku.part;
+      }
+    }
+  }
 });
 
 gcodeFileSchema.index({ name: 'text', gcodeFileName: 'text' });