fix(BE-48): improve adjustment history filtering and fix pointer conversion

- Add search parameter to adjustment history API
- Fix JOIN query logic to avoid duplicate JOINs
- Use EXISTS subquery for cleaner product/warehouse filtering
- Fix pointer conversion issue in slice iteration
- Improve query performance and code readability

internal/modules/inventory/adjustments/validations/adjustment.validation.go

@@ -11,7 +11,6 @@ type Create struct {
 type Query struct {
 	Page            int    `query:"page" validate:"omitempty,min=1"`
 	Limit           int    `query:"limit" validate:"omitempty,min=1,max=100"`
-	Search          string `query:"search" validate:"omitempty"`
 	ProductID       int    `query:"product_id" validate:"omitempty,min=0"`
 	WarehouseID     int    `query:"warehouse_id" validate:"omitempty,min=0"`
 	TransactionType string `query:"transaction_type" validate:"omitempty,oneof=increase decrease"`