refactor: update setRebaseRateMax function to clarify APR parameters and improve documentation (#2785)

Author: clement-ux

contracts/contracts/vault/VaultAdmin.sol

@@ -122,17 +122,19 @@ abstract contract VaultAdmin is VaultCore {
     // slither-disable-start reentrancy-no-eth
     /**
      * @notice Set a yield streaming max rate. This spreads yield over
-     * time if it is above the max rate.
-     * @param yearlyApr in 1e18 notation. 3 * 1e18 = 3% APR
+     * time if it is above the max rate. This is a per rebase APR which 
+     * due to compounding differs from the yearly APR. Governance should 
+     * consider this fact when picking a desired APR
+     * @param apr in 1e18 notation. 3 * 1e18 = 3% APR
      */
-    function setRebaseRateMax(uint256 yearlyApr)
+    function setRebaseRateMax(uint256 apr)
         external
         onlyGovernorOrStrategist
     {
         // The old yield will be at the old rate
         _rebase();
         // Change the rate
-        uint256 newPerSecond = yearlyApr / 100 / 365 days;
+        uint256 newPerSecond = apr / 100 / 365 days;
         require(newPerSecond <= MAX_REBASE_PER_SECOND, "Rate too high");
         rebasePerSecondMax = newPerSecond.toUint64();
         emit RebasePerSecondMaxChanged(newPerSecond);