Transactions directly from the wallets

[dobosmarton]

For now, the users need to faucet the tokens on the platform before swapping. This is not the right way to build a DEX. We should support any token transaction directly from the user's wallet.

At first, let's have only one liquidity pool with predefined tokens but the tokens have to be valid tokens. We will have a new issue for creating new liquidity pools dynamically.

Steps

1. Research about the topic, how works these kinds of transactions. Keep in mind that we have liquidity pools and the swap mechanism needs to work based on the available liquidity pools.

2. Solidity smart contract implementation.

Exmaples

1. Trading Joe Avalanche DEX: https://github.com/traderjoe-xyz/joe-core

2. Pangolin Avalanche DEX: https://github.com/pangolindex/exchange-contracts

3. Uniswap: https://github.com/Uniswap/v2-core (we can use the v2 because probably it is simpler than v3)