Multi Injected Provider Discoverability (similar to EIP-6964)

[ryanleecode]

Tasks

Beta Give feedback

1. UI (DApp) to present available providers
2. UI (DApp) to select/switch an available provider
3. Design spec and implement with CustomEvent (~~or RPC messages~~) #2136
   +0

[ryanleecode]

remaing work is to update to new polkadot provider spec