-- Add tool_change_minutes column to planning_job table
-- Allows per-job override of workstation buffer (Tool change time in minutes)
-- If NULL, uses default buffer from workstation type (FM=60, LASER=15, CNC=30)

ALTER TABLE llx_planning_job
ADD COLUMN tool_change_minutes INT NULL DEFAULT NULL AFTER estimated_hours;

-- Index added via application queries if needed
-- No FK required (purely internal override, not a reference)
