lotus-wallet: Add interactive mode

[magik6k]

Nice for things like looking at decoded message params on a secureish device before passing to ledger

[magik6k]

Example prompt:

ACTION: WalletSign - Sign a message/deal
ADDRESS: f1...
TYPE: message
Message JSON: {
  "Version": 0,
  "To": "f2...",
  "From": "f1....",
  "Nonce": 3,
  "Value": "0",
  "GasLimit": 427524,
  "GasFeeCap": "1637334214",
  "GasPremium": "11372",
  "Method": 2,
  "Params": "hEIAY0AAQK==",
  "CID": {
    "/": "baf..."
  }
}
Value: 0 FIL
Max Fees: 0.069999999997297 FIL
Max Total Cost: 0.069999999997297 FIL
Method: Propose
Params: {
  "To": "f099",
  "Value": "0",
  "Method": 0,
  "Params": null
}
        MultiSig Proposal Value: 0 FIL
        MultiSig Proposal Hex Params: 
        MultiSig Proposal Method: Send
        MultiSig Proposal Params: {}

Accept the above? (Yes/No):

[arajasek]

Approved with one nit (and needs rebasing).

Might also be good to docs folks attention?