docs: fix typos across source and test contracts

- BGT.sol:296 — 'gaurentees' → 'guarantees'
- IFeeCollector.sol:25 — 'transfered' → 'transferred'
- BlockRewardController.sol:235 — 'gauranteed' → 'guaranteed'
- RewardVault.t.sol:307 — 'afftects' → 'affects'
- BGTStaker.t.sol:154 — 'afftects' → 'affects'

Found during security audit of RewardVault, BGT, and WBERAStakerVault.

Author: sailorpepe

src/pol/BGT.sol

@@ -293,7 +293,7 @@ contract BGT is IBGT, ERC20VotesUpgradeable, OwnableUpgradeable, Multicallable {
         // `withdraw` will fail with zero amount.
         if (amount == 0 || !_checkEnoughTimePassed(blockNumberLast, dropBoostDelay)) return false;
         unchecked {
-            // queue drop boost gaurentees that the user has enough boosted balance to drop
+            // queue drop boost guarantees that the user has enough boosted balance to drop
             boosted[user][pubkey] -= amount;
             // `totalBoosts` >= `userBoosts[user].boost` >= `boosted[user][validator]`
             totalBoosts -= amount;

src/pol/interfaces/IFeeCollector.sol

@@ -22,7 +22,7 @@ interface IFeeCollector is IPOLErrors {
 
     /// @notice Emitted when the `PayoutToken` is donated.
     /// @param caller Caller of the `donate` function.
-    /// @param amount The amount of payout token that is transfered.
+    /// @param amount The amount of payout token that is transferred.
     event PayoutDonated(address indexed caller, uint256 amount);
 
     /// @notice Emitted when the fees are claimed.

src/pol/rewards/BlockRewardController.sol

@@ -232,7 +232,7 @@ contract BlockRewardController is IBlockRewardController, OwnableUpgradeable, UU
 
         emit BlockRewardProcessed(pubkey, nextTimestamp, base, reward);
 
-        // Use the beaconDepositContract to fetch the operator, Its gauranteed to return a valid address.
+        // Use the beaconDepositContract to fetch the operator, Its guaranteed to return a valid address.
         // Beacon Deposit contract will enforce validators to set an operator.
         address operator = beaconDepositContract.getOperator(pubkey);
         if (base > 0) bgt.mint(operator, base);

test/pol/BGTStaker.t.sol

@@ -151,7 +151,7 @@ contract BGTStakerTest is POLTest, StakingTest {
         assertApproxEqAbs(bgtStaker.earned(user), expectedEarned, 2e2);
     }
 
-    /// @dev Changing rewards duration during reward cycle afftects users staking in different times.
+    /// @dev Changing rewards duration during reward cycle affects users staking in different times.
     function test_SetRewardsDurationDuringCycleMultipleUsers() public {
         address user2 = makeAddr("user2");
         uint256 blockTimestamp = vm.getBlockTimestamp();

test/pol/RewardVault.t.sol

@@ -304,7 +304,7 @@ contract RewardVaultTest is DistributorTest, StakingTest {
         assertApproxEqAbs(vault.earned(user), expectedEarned, 2e2);
     }
 
-    /// @dev Changing rewards duration during reward cycle afftects users staking in different times.
+    /// @dev Changing rewards duration during reward cycle affects users staking in different times.
     function test_SetRewardsDurationDuringCycleMultipleUsers() public {
         address user2 = makeAddr("user2");
         uint256 blockTimestamp = vm.getBlockTimestamp();