Property Palette UI

[Ichthyostega]

As a Lumiera user,
I want parameter manipulation UIs to be managed automatically with allocation of tiles in the UI
in order to keep the most relevant properties accessible and remove clutter

Feature draft

When working and refining an edit, a huge amount of settings and parameters will be manipulated, controlled and revised. These are associated with local and global settings, as well as effects and transitions attached at various places. Typically, a common set of frequently used parameters emerges, complemented by a constant flow of one-time visited settings. Most established UI allocation schemes fall notoriously short on this usage pattern: either the one-time settings usurp and displace the commonly used parameters, or the scarce UI screen estate gets flooded with mostly irrelevant controls, turning repeated adjustments and fine-tuning into a nuisance.

We need a custom UI component to display a collection of sub panes with information and manipulation widgets. There needs to be a scheme to allocate a slot on this palette, and there needs to be a focus concept, allowing to navigate the detail panes within the palette, and to expand/collapse elements currently not in focus.

This is a challenging and complex task, as this property palette is likely to become one of the central elements of the Lumiera UI, alongside with the timeline #955