Added IOwnable interface to support integrations

src/interfaces/IOwnable.sol

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: LicenseRef-BUSL
+pragma solidity 0.8.28;
+
+/// @title IOwnable
+/// @notice interface for Ownable to support integrations
+interface IOwnable {
+    ///@notice function that returns owner address
+    function owner() external view returns(address);
+}

src/spoke/TreasurySpoke.sol

@@ -1,10 +1,14 @@
 // SPDX-License-Identifier: LicenseRef-BUSL
 pragma solidity 0.8.28;
 
+/// OwnableUpgradeable is only imported to override function owner defined in IOwnable.sol
+import {OwnableUpgradeable} from 'src/dependencies/openzeppelin-upgradeable/OwnableUpgradeable.sol';
 import {Ownable2StepUpgradeable} from 'src/dependencies/openzeppelin-upgradeable/Ownable2StepUpgradeable.sol';
 import {SafeERC20, IERC20} from 'src/dependencies/openzeppelin/SafeERC20.sol';
 import {MathUtils} from 'src/libraries/math/MathUtils.sol';
 import {IHubBase} from 'src/hub/interfaces/IHubBase.sol';
+/// IOwnable is only imported to override function owner defined in IOwnable.sol
+import {IOwnable} from 'src/interfaces/IOwnable.sol';
 import {ITreasurySpoke} from 'src/spoke/interfaces/ITreasurySpoke.sol';
 
 /// @title TreasurySpoke
@@ -18,6 +22,14 @@ abstract contract TreasurySpoke is ITreasurySpoke, Ownable2StepUpgradeable {
   /// @dev To be overridden by the inheriting TreasurySpoke instance contract.
   function initialize(address owner) external virtual;
 
+  /* function that overrides function owner defined in IOwnable.sol
+  using secure code of OwnableUpgradeable
+  and propagates its effects to contracts inherited from TreasurySpoke */
+  function owner() public view override(IOwnable, OwnableUpgradeable) returns(address) {
+    /// Call secure code of OwnableUpgradeable
+    return super.owner();
+  }
+
   /// @inheritdoc ITreasurySpoke
   function supply(
     address hub,

src/spoke/interfaces/ITreasurySpoke.sol

@@ -1,10 +1,12 @@
 // SPDX-License-Identifier: LicenseRef-BUSL
 pragma solidity ^0.8.0;
 
+import {IOwnable} from 'src/interfaces/IOwnable.sol';
+
 /// @title ITreasurySpoke
 /// @author Aave Labs
 /// @notice Interface for the TreasurySpoke.
-interface ITreasurySpoke {
+interface ITreasurySpoke is IOwnable {
   /// @notice Supplies a specified amount of the underlying asset to the specified Hub.
   /// @dev The Spoke pulls the underlying asset from the caller, so prior approval is required.
   /// @param hub The address of the Hub.