Add tokens/transfer-hook-transfer-switch/anchor

[krishnaagrawal7508]

1. Anchor program that allows for the toggling of transfer capabilities for a specific token mint. The implementation includes a transfer switch that can be enabled or disabled based on a specific account's state. When the switch is enabled, token transfers can proceed; when disabled, token transfers are halted, allowing for enhanced control over token management.

2. The tests included utilize solana-bankrun to simulate token transfers under various conditions. The tests cover the following scenarios:

• Successful Token Transfer: A token transfer is executed when the transfer switch is enabled. The test checks that the transfer completes successfully and that balances are updated accordingly.
• Transfer Denied: A token transfer attempt is made with the transfer switch disabled. The test verifies that the transaction fails as expected, demonstrating that the toggle effectively prevents transfers.
• Toggle Functionality: Tests for toggling the transfer switch, ensuring that the switch can be enabled and disabled appropriately and that the correct state is maintained.