As a user, I want that the symbols in the layer tree follow common practices, so that I can easily see and change the visibility state for each layer.
Acceptance criteria
[ ] Given I am a user and I am editing a MapContext, when I look at a layer node without rendering source, I want that the layer has a light-gray eye symbol with a slash.
[ ] Given I am a user and I am editing a MapContext, when I look at an inactive layer node with rendering source, I want that the layer has a black eye symbol with a slash.
[ ] Given I am a user and I am editing a MapContext, when I look at an fully active layer node with rendering source (the layer and all descendants are set to visible), I want that the layer has a black eye symbol.
[ ] Given I am a user and I am editing a MapContext, when I look at a layer node with rendering source that is partly visible (the layer and some, but not all descendants are set to visible), I want that the layer has a black eye-low-vision symbol.
[ ] Given I am a user and I am editing a MapContext, when I click on the eye symbol of a layer without rendering source, I want that nothing happens.
[ ] Given I am a user and I am editing a MapContext, when I click on the eye symbol of a layer with rendering source that is not active, I want that the layer and it's descendants are set to visible.
[ ] Given I am a user and I am editing a MapContext, when I click on the eye symbol of a layer with rendering source that is not active, I want that the ancestors visibility state is adapted.
[ ] Given I am a user and I am editing a MapContext, when I click on the eye symbol of a layer with rendering source that is partly active, I want that the layer and it's descendants are set to visible.
Environment
User Story
As a user, I want that the symbols in the layer tree follow common practices, so that I can easily see and change the visibility state for each layer.
Acceptance criteria