feat(launchpad): node actions

[mazzi]

Description

• Changes on node-manager to be less verbose.
• Now we can start/stop, add, remove individual nodes. For this we implemented a locking mechanism (semaphore) per node (locked on NodeItem).
• Added validations when adding nodes regarding amount of nodes and available disk space.
• Changed footer style and behavior depending on the application state.
• Some minor error message formatting.
• Validation of some edge cases like operations without nodes.
• Changed the legend when upgrading nodes as is difficult to pass the amount of nodes between scenes.