Baking: Update baker keys

[jens-concordium]

Task description

In case the user loses the baker keys, or if the baker keys are compromised, it should be possible to generate and submit a new set of keys. This can be done with the Update baker keys flow.

The Update baker keys flow can be accessed from the drop down on the baker status page.

The flow can be found in the box called "Update baker keys" in Figma.

The Update baker keys flow updates nothing but the baker keys, and for this reason the user doesn't have to input anything during the flow.

The Update baker keys flow:

• First the user is met with a carousel explaining baker concepts, and what to do with the baker keys.
• Next the baker keys are generated automatically. When the user press the button called "Export baker keys" on the page displaying the newly generated baker keys, the user will be met with a notification that reminds the user that this is the only chance to access to the keys.
• Continuing from the notification, the user will be able to export and save the baker keys somewhere, using the OS prompt.
• After exporting the keys, the user will see the pre-submission ticket of the transaction.
• Continuing from there, the transaction will be submitted and the transaction ticket will now also display the transaction hash. Pressing "Finish" will show the user a notification, telling them that the new keys will take effect from the next pay day, which also means the node should be restarted with the new keys as close to the next pay day as possible. Pressing Okay on the notification, will take the user to the baker status page.

[jens-concordium]

Note: After generating the baker credentials / baker keys, the baker ID should be added to the credentials. The baker ID can be retrieved with a query to the wallet-proxy.