UpdateAsync only applied WorkOrderType when it had a value, so once a
template was restricted to one work order type no request could make it
trade-generic again. The DTO now records whether workOrderType was present
in the body: omitting it keeps the stored value, an explicit null clears
it, and a concrete value sets it. The templates page echoes the stored
legacy fields on PUT, so its behaviour is unchanged.
Adds an extra safety note and an ordered procedure list to completion
document templates, name search, creator and last-updated audit fields,
a tenant-scoped count of open work orders that depend on a template, and
a delete that unlinks Services while they keep requiring a document.
Writes are gated by the create/edit/delete completion template team
permissions instead of the Admin role.