Initial release: RMA Automation plugin with repair parts tracking

Features:
- Automatic stock status updates based on return order outcomes
- Repair parts allocation and consumption tracking
- Configurable status mappings for each outcome type
- React-based UI panel for managing repair parts
- Location display for easy part retrieval
- Available stock filtering (excludes allocated items)

inventree_rma_plugin/models.py

@@ -0,0 +1,85 @@
+"""Database models for the RMA Automation plugin."""
+
+from django.db import models
+
+
+class RepairStockAllocation(models.Model):
+    """Tracks stock items allocated for repair work on return order line items.
+
+    When a return order line item requires repair, stock items (replacement parts)
+    can be allocated to it. These are consumed when the return order is completed.
+    """
+
+    return_order_line = models.ForeignKey(
+        'order.ReturnOrderLineItem',
+        on_delete=models.CASCADE,
+        related_name='repair_allocations',
+        help_text='The return order line item this allocation is for',
+    )
+
+    stock_item = models.ForeignKey(
+        'stock.StockItem',
+        on_delete=models.CASCADE,
+        related_name='repair_allocations',
+        help_text='The stock item being allocated for repair',
+    )
+
+    quantity = models.DecimalField(
+        max_digits=15,
+        decimal_places=5,
+        default=1,
+        help_text='Quantity of stock allocated',
+    )
+
+    consumed = models.BooleanField(
+        default=False,
+        help_text='Whether this allocation has been consumed',
+    )
+
+    created = models.DateTimeField(
+        auto_now_add=True,
+        help_text='When this allocation was created',
+    )
+
+    notes = models.CharField(
+        max_length=500,
+        blank=True,
+        default='',
+        help_text='Optional notes about this allocation',
+    )
+
+    class Meta:
+        """Model metadata."""
+
+        app_label = 'inventree_rma_plugin'
+        verbose_name = 'Repair Stock Allocation'
+        verbose_name_plural = 'Repair Stock Allocations'
+
+    def __str__(self):
+        """String representation."""
+        return f'{self.quantity} x {self.stock_item} for {self.return_order_line}'
+
+    @property
+    def return_order(self):
+        """Get the parent return order."""
+        return self.return_order_line.order
+
+    def clean(self):
+        """Validate the allocation."""
+        from django.core.exceptions import ValidationError
+
+        # Check stock item has sufficient quantity
+        if self.stock_item and not self.consumed:
+            available = self.stock_item.quantity
+            # Subtract other allocations for this stock item (excluding self)
+            other_allocations = RepairStockAllocation.objects.filter(
+                stock_item=self.stock_item,
+                consumed=False,
+            ).exclude(pk=self.pk)
+            allocated = sum(a.quantity for a in other_allocations)
+            available -= allocated
+
+            if self.quantity > available:
+                raise ValidationError({
+                    'quantity': f'Only {available} available (already allocated: {allocated})',
+                })