Sort unassigned tasks in the dispatch panel

[Atala]

So we modified the dispatch panel to be able to be able to sort unassigned tasks; which broke the previous behaviour

Before :

• by default tasks are sorted by beginning of delivery slot
• you can sort them by "dropoff asc" or "dropoff desc" -> it sorts the dropoff by beginning of delivery slot and then insert the pickup right before the dropoff
• tasks can not by sorted by DnD in the unassigned tasks column

After the changes :

• INITIALLY tasks are sorted beginning of delivery slot
• tasks added aftewards are APPENDED to the unassigned tasks list no matter when they need to be done (which is a problem for foodtech Dispatch pannel : An order is not in chronological order coopcycle-web#4153). Why is that ? because we track the order of unassigned tasks now so we can not insert them where we want
• sort by dropoff asc and dropoff desc is broken now ( Sorting unassigned tasks is broken in dashboard coopcycle-web#4162 )

Questions for next :

• where do we insert newly created tasks ?
• should we keep "dropoff asc" and "dropoff desc" mode above?
• In order to handle lots of unassigned tasks As a dispatcher I want to be able to sort unassigned tasks coopcycle-web#4137 to be implemented

a possibility would be that when you click sort you "force sort" the tasks (for foodtech for example) so they keep apearing sorted as default but you can not reorder them.

[Paul-Eraman-CoopCycle]

In this url: https://demo.coopcycle.org/admin/dashboard

we have all our unassigned tasks on the top right, and we can either chose to see them displayed "by groups", by time of dropoff in ascending order, by time of dropoff in descending order, or "all"

Firstly, these 4 options are strange and not very well explained. I am not even sure what the first or last one means.

Then, we have. a filter modal that can filter by tag, toggle visualization of tasks assigned to specific riders, filter by time, and has a few miscelaneous options.

The question is how to organize the dashboard so that these options are clearer, as well as decide what types of visualizations we want.

It is clear that there needs to be:

1. a foodtech "default" state based on those particular needs
2. ability to filter both for things as well as to not see things
3. save formats that the dashboard is visualized in
4. centralize all options in a more contained visual system

[Atala]

actually what is confusing is that 1st and 4th options are to show groups or not. either the groupped tasks are contained in folders/groups either theses folters/groups are expanded.

[Atala]

i have give some thought about it, and here it is:

• what we had before is kind of "locked sort" (with three different choices) = unassigned tasks are modified -> sort automatically
• now we have implemented "manual sorting" which is another option to add to the menu

so we could have a sorting menu with four options :

• manual
• "group by dropoff" asc (it sorts only the dropoffs and groups the pickup with it)
• "group by dropoff" desc (it sorts only the dropoffs and groups the pickup with it)
• by beginning of deliveery slot (doesnt group orders together)

in case of "manual sorting" we need to discuss where we insert the new tasks (coming from dashboard or from foodtech), either on top (prepend) or bottom (append) of the list.

also we can animate newly added tasks to highlight them (in any of the above cases).

[Atala]

Related #4196