add permit to escrow contracts

[alexcos20]

Add ERC20Permit Support to Escrow Contracts

Summary

This PR adds ERC20Permit (EIP-2612) support to both Escrow and EnterpriseEscrow contracts, allowing users to deposit tokens without requiring a separate approval transaction. This improves user experience by reducing gas costs and transaction complexity.

Motivation

Currently, users must perform two transactions to deposit tokens into escrow:

1. Approve the escrow contract to spend their tokens
2. Call the deposit function

With ERC20Permit support, users can combine these into a single transaction by providing a permit signature, eliminating the need for a separate approval transaction. This reduces gas costs and improves the user experience, especially for users interacting with the escrow contracts frequently.

How It Works

1. User signs a permit message off-chain (using EIP-712 structured data signing)
2. User calls depositWithPermit with the signature parameters
3. Contract calls permit on the token to approve itself
4. Contract calls internal _deposit function to complete the deposit
5. Same Deposit event is emitted as regular deposits

Security Features

1. Reentrancy Protection: Uses nonReentrant modifier
2. Signature Validation: ERC20Permit validates the signature automatically
3. Deadline Checking: ERC20Permit checks that the deadline hasn't expired
4. Safe Token Transfers: Uses SafeERC20 for all token operations
5. Same Validation: Uses the same internal _deposit function as regular deposits

[alexcos20]

WIP: deployments

[openzeppelin-code]

add permit to escrow contracts

Generated at commit: f977600b4b1fba3ccc98d9065de26444a853d908

🚨 Report Summary

	Severity Level	Results
Contracts	Critical High Medium Low Note Total	2 1 0 9 40 52
Dependencies	Critical High Medium Low Note Total	0 0 0 0 0 0

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For more details view the full report in OpenZeppelin Code Inspector