Improvement: Redesign Course Cards

[julian-wls]

Problem Description

Compared to the iOS app and the web app the dashboard of the Android app does not really fit. Course cards are designed in a different way on all other platforms.

Changes

This PR changes the design of the dashboard and restructures the logic behind course cards and how there are used in the grid layout:

• Redesign of the dashboard
  - new icon design for the top bar
  - new design for the course enrollment screen

This PR is related to #350, but doesn't close it yet, because I will create a follow up PR to add the recent section.

Steps for testing

Use Artemis test user 2 on TS to test the following:
- Scroll through the dashboard and check if there are any issues with the new design
- Click on an exercise below next exercise if there is any and check if you're redirected to that exercise
- Navigate to the course enrollment screen and check the design for the preview course items
- Login to TS1 or TS to check the Circular Progress that is visible for courses that have started exercises.


Screenshots

[FelberMartin]

I like this change, the feels much more consistent with web and iOS now 👌

I noticed one issue that has been there before, but maybe it makes sense to tackle it as part of this PR as it should not be a huge change:
The contrast on some course cards is quite bad (eg if the course color is yellow, see screenshot). I know this is also this way on the webapp, but I think we can do better. We could use a simple check with android.graphics.Color.luminance() to switch the text color to black for bright surfaces. What do you think?

[julian-wls]

I noticed one issue that has been there before, but maybe it makes sense to tackle it as part of this PR as it should not be a huge change: The contrast on some course cards is quite bad (eg if the course color is yellow, see screenshot). I know this is also this way on the webapp, but I think we can do better. We could use a simple check with android.graphics.Color.luminance() to switch the text color to black for bright surfaces. What do you think?

I agree with you, however I don't think it's a good idea to deviate from the design of the other platforms. I think all platforms should be consistent regarding this. But I 100% agree with you. My idea would be to maybe discuss this in the meeting. I don't think it's our call to make.

[eylulnc]

Its looking really good and agree with its alignment to web and iOS now 😊.
Works as described ✅