feat: methods for transfer association and approval from the IHTS

[arianejasuwienas]

Description:

Adding the implementation of the methods from the IHederaTokenService interface. I will allow users to perform token-based operations by interacting with the HTS contract at the 0x167 address. The token-based operations introduced in this PR were already implemented on the token side through interfaces compatible with IERC721, IERC20, and IHRC719, but they have now been extended to support HTS calls as well.

For example, in addition to transferring a fungible token using the IERC20 interface

IERC20(token).transferFrom(sender, recipient, amount);  

you can now perform the same operation via the HTS interface

IHederaTokenService(address(0x167)).transferToken(token, sender, recipient, amount);

Related issue(s):

#151

Notes for reviewer:

Checklist

• Documented (Code comments, README, etc.)
• Tested (unit, integration, etc.)

[acuarica]

nice work, it's looking good

[acuarica]

looking good, almost there

[acuarica]

Nice stuff!