Redesign flows and user roles on dashboard

### Why

We need to clarify what the dashboard should say as users change roles from DRep to Direct Voter to Delegator, and when they retire and un-retire. Currently, there is confusion due to the use of the cards for history, etc. See #912 and #763 for more context.

### What

This is an improvement in the dashboard, which will probably prove to be essential, as the issues are pretty significant in the UX.

### How

There are a few stages to this issue:

First is creating a matrix of role changes (DRep => Direct Voter => retired, etc).
This matrix or flow diagram would show the steps that users make to change roles, and how that effects their delegation, voting power, and retirement status.

The second part of the design is to make dashboard screens that match these states,

the third is what changes to the flows are needed - if any - to make things happen.

One idea that Lorenzo and I had was when someone becomes a DRep, they automatically delegate all their ada-power to themselves. This will stop the strange "i am a drep with all my voting power delegated to someone else" dashboard state.

(Currently, when someone becomes a Direct Voter, they automatically delegate all their ada-power to themselves)

What needs to happen in general:

- If a DRep becomes a Direct Voter, they lose all their ‘delegated’ voting power, and their 'own ADA balance becomes their Direct Voter Voting Power
- If a Drep retires, they lose all their 'delegated' voting power, and all voting power
- if a Drep un-retires, they regain all remaining voting power that was delegated to them previously, and they also assume the same DRep ID
- As we do not store DRep names in the chain, a re-registering DRep could create themselves a new Drep name.
- The re-registering DRep, when they go to re-register, and if the data is available off chain, will see their previous DRep registration data pre-populated
- If a Direct Voter retires, they lose all voting Power and their Voting Power is delegated automatically to "Abstain"

Design deliverables:

1. A matrix that shows all states of Drep, delegation, Direct Voter, with their voting power, voting rights, etc
- I’ve made a start in Miro - but it’s not complete - https://miro.com/app/board/uXjVMF-hg-I=/?moveToWidget=3458764580467477596&cot=14

2. A wireframe or design to accompany each stage (this will be after we have analysed the matrix fully, so it will be even a different github ticket.

3. Other stuff that will need changing such as flows, etc