Update Natspec for FeeAdapter (#10969)

packages/protocol/contracts-0.8/stability/interfaces/IFeeCurrencyAdapter.sol

@@ -2,22 +2,49 @@
 pragma solidity >=0.8.7 <0.8.20;
 
 interface IFeeCurrencyAdapter {
+  /**
+   * @return The address of the adapted token.
+   */
   function getAdaptedToken() external view returns (address);
 
+  /**
+   * @return The multiplier that should be used when upscaling and downscaling. This is the result of 10**(expectedDecimals - getAdaptedToken().decimals()).
+   */
   function digitDifference() external view returns (uint96);
 
+  /**
+   * @return The amount that is debited after calling debitGasFees() and before creditGasFees().
+   */
   function debited() external view returns (uint256);
 
+  /**
+   * @return The name of the adapted token.
+   */
   function name() external view returns (string memory);
 
+  /**
+   * @return The symbol of adapted token.
+   */
   function symbol() external view returns (string memory);
 
-  function expectedDecimals() external view returns (uint8);
-
+  /**
+   * @return The decimals expected by the vm.
+   */
   function decimals() external view returns (uint8);
 
+  /**
+   * @return Same as decimals.
+   */
+  function expectedDecimals() external view returns (uint8);
+
+  /**
+   * @notice Same as debitGasFees in IFeeCurrency, always using the number of decimals the evm expects.
+   */
   function debitGasFees(address from, uint256 value) external;
 
+  /**
+   * @notice Same as creditGasFees in IFeeCurrency, always using the number of decimals the evm expects.
+   */
   function creditGasFees(
     address refundRecipient,
     address tipRecipient,