[Feature] allow read only mode

[SvenMeyer]

(To start with), I would like to use the CLI in read-only mode to get a list of my open positions.
However, changing the private key to a real one is needed to setup the config

$ perp position -t 0x3aFxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Creating New Config File
Would you like to change your RPC URL? (y/n)
y
Please provide an RPC URL:
https://endpoints.omniatech.io/v1/op/mainnet/d33exxxxxxxxxxxxxxxxxxxxxxx
New RPC URL has been validated and works. Saving to config file now...
Your Chain ID is set to: 10
Would you like to change your Chain ID? (y/n)
n
Would you like to change your key? (y/n)
n
Would you like to change your key? (y/n)
n
Error: Failed to parse private key: HexError(InvalidHexCharacter { c: 'N', index: 0 })

Location:
    src/utils.rs:49:22

$ perp position -t 0x3aFxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Would you like to change your key? (y/n)
n
Would you like to change your key? (y/n)
y
Please provide the 64-character private key: (Without the 0x prefix)
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
Key updated
Error: Failed to parse private key: EcdsaError(signature::Error { source: None })

Location:
    src/utils.rs:49:22

[brendanwenzel]

Yes, that's something that I was already thinking about. Will work on adding that over the weekend.

In the meantime, I've been using the 1 private key as a read-only key:
0000000000000000000000000000000000000000000000000000000000000001

[brendanwenzel]

@SvenMeyer Would an acceptable solution be to make a default private key if the user either chooses no to changing the key or if the key given has an error? That seems to be the easiest to implement.

[lkblkb]

@brendanwenzel works for me 😁

[brendanwenzel]

@brendanwenzel works for me 😁

Thank you @lkblkb for the feedback. Going to shoot to have this pushed by Tuesday.