Usability improvements for tutorial 1

[fynnos]

Fixes #673 #668 #665 #663

1. code description is now optional (allowing faster code creation)
2. delete dialogs now explicitly use 'delete' as action, with red icon button
3. move 'delete project' to a new 'danger zone' requiring typing the project name
4. active tab in sidebar is now highlighted stronger
5. analysis cards are colored blue-ish