Feat: Enable smart confidential transfers in agentkit

[nlok5923]

This pull request introduces significant updates to the agentkit-core package, including the removal of the CONTRIBUTING.md file, the addition of new dependencies, and the implementation of two new actions: SmartConfidentialTransferAction and SmartDepositAction. These changes enhance the functionality for confidential token transfers and deposits on Avalanche C-Chain. Below is a breakdown of the most important changes:

Documentation Changes:

• Removal of CONTRIBUTING.md: The contributing guide has been entirely removed, including setup instructions, development tools, and guidelines for adding actions and toolkits.

Dependency Updates:

• Addition of petcrypt-js-lite: A new dependency (petcrypt-js-lite version 1.0.8) has been added to support confidential token transfers.

New Actions for Confidential Transfers and Deposits:

Confidential Transfers:

• SmartConfidentialTransferAction Implementation: Added a new action to perform confidential transfers of USDC tokens on Avalanche C-Chain. This includes input validation, transaction creation, and confirmation handling.

Token Deposits:

• SmartDepositAction Implementation: Introduced an action to deposit USDC tokens for confidential transfers on Avalanche C-Chain. This includes approval and deposit transactions using gasless smart accounts.

Minor Guidance Update:

• getBalanceAction Usage Guidance: Updated the usage guidance to clarify that the tool should not be used for private or confidential balances.