Widgets overview - Githubissues

This is an overview of essentials to resolve for a first public version of the widgets:

[x] Implement #59.
[x] Implement optional parameters. #71
[x] Implement #57.
[ ] #74
[ ] Show outputs using a vertical layout of checkboxes (instead of list, avoids need to use shift or ctrl ubttons)?
[ ] Show extended outputs as combo-box, so they are mostly hidden by default
[ ] Fix some UI logic around enabling/disabling buttons, make sure things can be run again, ...
[ ] Implement mappable widget wrapping arbitrary other widgets, where rows can be added/removed, yielding a tuple of parameter values. Probably add a mappable field to class Parameter to enable this.
[ ] Low hanging fruit for look&feel: Type formatting, description display, ...
[ ] Split out workflow&output selection to its own widget, make it displayable in a tab (param settings should be in second tab).
[x] Helper functions to create widgets, instead of creating a single one in the module (some notebooks will need to create multiple workflow widgets). #68
[ ] Parameter that can take existing Python object as input. The widget should parse the global namespace (maybe similar to https://github.com/scipp/scipp/edit/main/src/scipp/object_list.py?), providing a drop-down list of objects to select from. May be filtered by type.
[ ] Saving parameters and load them
[x] Add tests

scipp / essreduce