chore: address contract lints

Author: MarcosNicolau

contracts/src/core/AggregationModePaymentService.sol

@@ -5,30 +5,56 @@ import {Initializable} from "@openzeppelin-upgrades/contracts/proxy/utils/Initia
 import {OwnableUpgradeable} from "@openzeppelin-upgrades/contracts/access/OwnableUpgradeable.sol";
 import {UUPSUpgradeable} from "@openzeppelin-upgrades/contracts/proxy/utils/UUPSUpgradeable.sol";
 
+/**
+ * @title AggregationModePaymentService
+ * @author Aligned Layer
+ * @notice Handles deposits that grant time-limited access to aggregation services.
+ */
 contract AggregationModePaymentService is Initializable, OwnableUpgradeable, UUPSUpgradeable {
-    // 24hs
-    uint256 constant paymentValidUntilSeconds = 86400;
+    /// @notice for how much time the payment is valid in seconds (86400s = 24hs)
+    uint256 public constant PAYMENT_VALID_UNTIL_SECONDS = 86400;
 
-    event UserPayment(address user, uint256 amount, uint256 from, uint256 until);
+    /**
+     * @notice Emitted when a user deposits funds to purchase service time.
+     * @param user Address that sent the payment.
+     * @param amount Native token amount paid.
+     * @param from Timestamp when the payment was recorded.
+     * @param until Timestamp until when the payment is valid.
+     */
+    event UserPayment(address user, uint256 indexed amount, uint256 indexed from, uint256 indexed until);
 
     error InvalidDepositAmount(uint256 amount);
 
+    /**
+     * @notice Disables initializers for the implementation contract.
+     */
     constructor() {
         _disableInitializers();
     }
 
+    /**
+     * @notice Initializes the contract and transfers ownership to the provided address.
+     * @param _owner Address that becomes the contract owner.
+     */
     function initialize(address _owner) public initializer {
         __Ownable_init();
         __UUPSUpgradeable_init();
         _transferOwnership(_owner);
     }
 
+    /**
+     * @notice Ensures only the owner can authorize upgrades.
+     * @param newImplementation Address of the new implementation contract.
+     */
     function _authorizeUpgrade(address newImplementation)
         internal
         override
         onlyOwner // solhint-disable-next-line no-empty-blocks
     {}
 
+    /**
+     * @notice Accepts payments and validates they meet the minimum requirement.
+     */
     receive() external payable {
         uint256 amount = msg.value;
 
@@ -37,6 +63,6 @@ contract AggregationModePaymentService is Initializable, OwnableUpgradeable, UUP
             revert InvalidDepositAmount(amount);
         }
 
-        emit UserPayment(msg.sender, amount, block.timestamp, block.timestamp + paymentValidUntilSeconds);
+        emit UserPayment(msg.sender, amount, block.timestamp, block.timestamp + PAYMENT_VALID_UNTIL_SECONDS);
     }
 }