A young constable killed in a horror car crash while on duty has been remembered as a talented, optimistic and calm recruit on a day of police mourning.On National Police Remembrance Day, Mia Lay, 20, was honoured alongside Victorian colleagues killed by Dezi Freeman at a rural property last year.Ms Lay had been on the force for 16 months before dying, crashing in pursuit of a stolen car at Redfern in Sydney on Friday.Attendees talked of her youth and dedication at a solemn service in front of the Police Wall of Remembrance in Sydney's Domain on Tuesday morning.Premier Chris Minns...