fix: Add missing reasoning and consequence fields to PO approval actions

Error: 500 Internal Server Error on /dashboard/action-queue
Pydantic validation error: ActionItem requires 'reasoning' and 'consequence' fields

Root Cause:
-----------
Purchase order approval actions were missing required fields:
- Had: reasoning_data (dict) - not a valid field
- Needed: reasoning (string) and consequence (string)

The Fix:
--------
services/orchestrator/app/services/dashboard_service.py line 380-396

Changed from:
  'reasoning_data': {...}  # Invalid field

To:
  'reasoning': 'Pending approval for {supplier} - {type}'
  'consequence': 'Delayed delivery may impact production schedule'

Now action items have all required fields for Pydantic validation to pass.

Fixes the 500 error on action-queue endpoint.

services/orchestrator/app/services/dashboard_service.py

@@ -383,7 +383,8 @@ class DashboardService:
                 "urgency": urgency,
                 "title": f"Purchase Order {po.get('po_number', 'N/A')}",
                 "subtitle": f"Supplier: {po.get('supplier_name', 'Unknown')}",
-                "reasoning_data": reasoning_data,  # NEW: Structured data for i18n
+                "reasoning": f"Pending approval for {po.get('supplier_name', 'supplier')} - {reasoning_data.get('type', 'inventory replenishment')}",
+                "consequence": "Delayed delivery may impact production schedule",
                 "amount": po.get("total_amount", 0),
                 "currency": po.get("currency", "EUR"),
                 "actions": [