feat: add ITreasuryModule interface for treasury modules

contract/src/ITreasuryModule.cairo

@@ -0,0 +1,37 @@
+# ITreasuryModule.cairo
+
+"""
+Interface for Treasury Modules.
+Defines standard functions for treasury modules to interact with governance modules.
+"""
+
+@contract_interface
+namespace ITreasuryModule:
+    """
+    Executes a transfer of funds from the treasury.
+    Args:
+        token_address (ContractAddress): The address of the token to transfer.
+        recipient (ContractAddress): The address of the recipient.
+        amount (u256): The amount to transfer.
+    """
+    func execute_transfer(token_address: ContractAddress, recipient: ContractAddress, amount: u256):
+    end
+
+    """
+    Sets the governance module that can control this treasury.
+    Args:
+        new_governance_module (ContractAddress): The address of the new governance module.
+    """
+    func set_governance_module(new_governance_module: ContractAddress):
+    end
+
+    """
+    Returns the balance of a given token in the treasury.
+    Args:
+        token_address (ContractAddress): The address of the token to check.
+    Returns:
+        u256: The balance of the token.
+    """
+    func get_balance(token_address: ContractAddress) -> (balance: u256):
+    end
+end