What

Change this

type WorkspaceBuild struct {
    ...
    Deadline time.Time `json:"deadline"`
    ...

To this:

type WorkspaceBuild struct {
    ...
    Deadline *time.Time `json:"deadline"`
    ...

Why

The FE currently needs to check for the zero-value of time.Time for 'falsey' values.
Making this a pointer would allow passing null and avoid this need.