More import script updates and fixes, better import_history tracking

inventory-server/db/config-schema.sql

@@ -184,6 +184,7 @@ CREATE TABLE IF NOT EXISTS import_history (
     start_time TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     end_time TIMESTAMP NULL,
     duration_seconds INT,
+    duration_minutes DECIMAL(10,2) GENERATED ALWAYS AS (duration_seconds / 60.0) STORED,
     records_added INT DEFAULT 0,
     records_updated INT DEFAULT 0,
     is_incremental BOOLEAN DEFAULT FALSE,

inventory-server/db/schema.sql

@@ -118,6 +118,7 @@ CREATE TABLE IF NOT EXISTS orders (
     status VARCHAR(20) DEFAULT 'pending',
     canceled TINYINT(1) DEFAULT 0,
     PRIMARY KEY (id),
+    UNIQUE KEY unique_order_line (order_number, pid),
     KEY order_number (order_number),
     KEY pid (pid),
     KEY customer (customer),