Pool keeps track of it's reserve

[Neylix]

Describe the problem you discovered

Currently the implementation means that the number of token in a pool + the number of token in its reserve address is exactly the amount that have been created on Archethic.
However if someone send tokens directly to the pool or the reserve address, then we cannot rely on there balance to ensure the 1:1 ratio of the bridge.

Describe the solution you'd like

To ease the calculation of this ration, the pool can have a new public variable "reserve" that must be update every time a swap is finished. So this variable should always be the exact amount that as been bridged

Epic

No response