Liquidity operations

[gztensor]

This PR is only an example, by no means is a final implementation. It shows how to add the following functionality:

• Adding user liquidity
• Removing user liquidity
• Viewing user liquidity and accrued fees

Testing on the local network:

1. Create and configure subnet:

• Give your coldkey 2000 TAO
• Call startCall
• Enable user liquidity: swap::setUserLiquidityEnabled

2. Add liquidity

$ btcli lq add --network=local
Enter the netuid to use: 2
Enter the wallet name (default): 
Enter the wallet hotkey name or ss58 address to use stake from: 5Eeq15e55UTfFcsw6kUNRhzRwTsAHciXk5sPajARWXxtjzyA

Enter the amount of liquidity: 1

Enter the liquidity position low price: 0.1 

Enter the liquidity position high price: 0.9

3. View added liquidity

$ btcli lq list --network=local
Enter the netuid to use: 2
Enter the wallet name (default): 
p = BittensorScaleType(value={'id': (2,), 'netuid': (2,), 'tick_low': (-23027,), 'tick_high': (-1053,), 'liquidity': 1000000000, 'fees_tao': {'bits': 0}, 'fees_alpha': {'bits': 0}})>
tick_low = {'liquidity_net': 1000000000, 'liquidity_gross': 1000000000, 'fees_out_tao': {'bits': 0}, 'fees_out_alpha': {'bits': 0}}
tick_high = {'liquidity_net': -1000000000, 'liquidity_gross': 1000000000, 'fees_out_tao': {'bits': 0}, 'fees_out_alpha': {'bits': 0}}
fees_in_range_tao = 0.0
fees_tao = 0.0000 τ
Position ID: 2
Position liquidity: 1.0000 τ
Price range:
   low:  0.10000002203192325
   high: 0.9000592042233925
Fees accrued:
   tao:   0.0000 τ
   alpha: 0.0000 τ

[thewhaleking]

@gztensor when do you expect this to be able to work on testnet or mainnet?

[bdmason]

I think these need to be halved to match the ticks used in rust