Resolve "Cleanup and improve themes"

Please make sure your MR is ready to be merged !

• You added the changes in CHANGELOG.md
• You described the MR as below

Changes :

• Same structure for resources and theme assets everywhere
• Missing cartridges labels
• Change band colors if necesarry
• Redraw and export assets if necesarry

Related to :

• link other PR or issues here

Closes #56 (closed)