Settle on a coordinated color scheme and design language for icons

[alice-i-cecile]

We want to synchronize colors between:

1. Goals
2. Actions
3. Crafting status
4. Signal kind
5. Abilities

There's matching variants in each (e.g. Ability::Lure and Goal::Lure), so these need to correspond correctly while being meaningfully distinct from their siblings.

Particularly important combinations (e.g. Push/Pull/Work) should be color-blind friendly too.

Spreadsheet seems like the only sensible way to plan this.

[alice-i-cecile]

Each of these variants should get a a standardized modifier that surrounds the symbol (e.g. a circle or hex) so we can communicate symbol kind and reuse the inner icons.

[alice-i-cecile]

Units, structures, and terraforming all need a modifier as well T_T