Make pre-release updates.

[0xBoringWozniak]

This pull request includes several changes to the hyperliquid package, focusing on refactoring constants, improving logging, and enhancing order handling and conversion functions. The most important changes include the introduction of API URL constants, improvements to the logging level, and the replacement of rounding functions with more precise conversion functions for order prices and sizes.

Refactoring and Constants:

• hyperliquid/consts.go: Introduced MAINNET_API_URL and TESTNET_API_URL constants to replace hardcoded URLs in getURL function.
• hyperliquid/client.go: Updated getURL function to use the new constants MAINNET_API_URL and TESTNET_API_URL.

Logging Improvements:

• hyperliquid/client.go: Set the logging level to Debug in the NewClient function.
• hyperliquid/client.go: Changed the debug method to use Debugf instead of Printf for better logging consistency.

Order Handling Enhancements:

• hyperliquid/exchange_service.go: Removed several order-related methods (MarketOrder, MarketOrderSpot, LimitOrder, ClosePosition, CancelOrderByOID, CancelAllOrdersByCoin, CancelAllOrders) to streamline the order handling process. [1] [2] [3]
• hyperliquid/exchange_service.go: Added helper functions for building EIP712 messages for bulk orders and single orders.

Conversion Functions:

• hyperliquid/convert.go: Replaced RoundOrderPrice and RoundOrderSize with PriceToWire and SizeToWire functions for more precise order price and size conversions.

Testing Enhancements:

• Move all tests to testnet (ref: Move all tests to testnet #8)
• hyperliquid/convert_test.go: Added unit tests for SizeToWire and PriceToWire functions to ensure their correctness.