feat: 月度模式全面参数化 - 移除硬编码日期，前后端按月动态查询

sql/etl_fact_inventory.sql

@@ -0,0 +1,34 @@
+-- Step 3: 填充 fact_inventory_snapshot 从盘点倒挤数据ETL
+-- 需要将 cost_unit_code 映射为 store_code，盘点数据中有 sales_store_code 可用
+
+INSERT INTO analytics.fact_inventory_snapshot (
+  store_code, material_code, snapshot_date, 
+  opening_quantity, opening_amount, 
+  purchase_quantity, purchase_amount, 
+  consumption_quantity, consumption_amount, 
+  ending_quantity, ending_amount, 
+  waste_quantity, waste_amount, 
+  transfer_in_quantity, transfer_out_quantity, 
+  inventory_days, is_negative, created_at
+)
+SELECT 
+  COALESCE(s.sales_store_code, i.cost_unit_code) AS store_code,
+  i.item_code AS material_code,
+  i.report_month AS snapshot_date,
+  i.opening_quantity, i.opening_amount,
+  i.purchase_quantity, i.purchase_amount,
+  i.consumption_quantity,
+  i.consumption_amount,
+  i.ending_quantity, i.ending_amount,
+  NULL::numeric AS waste_quantity,
+  COALESCE(i.return_loss_amount, 0) AS waste_amount,
+  NULL::numeric AS transfer_in_quantity,
+  NULL::numeric AS transfer_out_quantity,
+  NULL::numeric AS inventory_days,
+  i.is_negative_consumption AS is_negative,
+  now() AS created_at
+FROM inventory_cost_records i
+LEFT JOIN inventory_store_mapping s ON i.cost_unit_code = s.cost_unit_code
+WHERE i.report_month = DATE '2026-04-01'
+  AND i.item_code IS NOT NULL AND i.item_code != ''
+ON CONFLICT DO NOTHING;