Manually test hardware wallet support

[evan-forbes]

As far as I know, we've never actually tested hardware wallet support, we've always just relied on the cosmos-sdk. We need to test hardware wallet support and better understand if there's anything we can do to support it.

Ideally, hardware wallets would also be able to support signing PFDs, but that might be weird or not possible since we have to sign multiple versions of the protobuf encoded transactions.

[rootulp]

I verified that it is possible to add a key from Ledger (see #2014 (comment)). I will test that it is possible to submit a PFB with a Ledger. I expect it to work b/c now a user only needs to sign one transaction (no more multiple square sizes). Additionally the blob module has legacy Amino codec support which is needed for Ledger.

[liamsi]

I think, besides manual testing, we should also add a very minimalistic test in CI. IIRC, ledger also can be mocked away s.t. you can emulate a plugged in ledger in docker. (I think the manual tests are mainnet blocking, the CI tests are not though).

[rootulp]

I think the manual tests are mainnet blocking, the CI tests are not though

Agreed. CI tests would help us catch regressions so I think we should add. Created #2225 to track CI tests. Renamed this issue to track manual test.

[rootulp]

It works! Steps documented in this gist in case anyone wants to try it.