Remove tasksDoneToday collection

[tijlleenders]

Is your feature request related to a problem? Please describe.
In #1407 we implemented tasksHistory and tasksDoneToday collections, but the information from tasksDoneToday can also be queried from taskHistory - so it is actually not needed.

Describe the solution you'd like
Remove the tasksDoneToday collection - and send the required data for the scheduler from taskHistory:

For each goal that is sent to scheduler, filter/aggregate it down to:

• total_time_completed
• time_completed_in_last_7_days
• time_completed_today
• time_completed_in_future
  so that this can be taken into account by the scheduler.

Add these fields to the goal being sent to the scheduler.

Describe alternatives you've considered
Reducing the number of hours of the goal.
A. This is not correct. The goal represents the ambition, not the realization.
B. An option could be to include it as attribute(s) of the Goal (i.e. realizedHours). Keeping that accurate could get messy, due to the sliding window - so querying the tasksHistory table directly at schedule query time dynamically is simpler, without the indirection of the Goals collection.

Additional context
None.