What mechanisms is her department putting in place to stimulate the construction sector in responding to the lockdown as a result of the COVID-19 pandemic in order to bring about (a) a phased reopening of the sector, (b) (i) the drafting of plans and (ii) implementation and enforcement of risk and mitigation plans sector-wide to prevent infections on sites, (c) the reopening of support organisations (details furnished) and (d) a plan around the infrastructure development spending that forms part of the medium-term expenditure framework?