Add Dexscreener Data Source for Token Price Fetching

[Mide001]

Description

This PR integrates Dexscreener as a new data source to fetch the current price of any token on Base. Previously, when fetching token balances, only the number of tokens was returned without their USD value. This update ensures that we can retrieve the real-time price of tokens, making it easier to calculate their actual worth.

Fixes # (issue)

This resolves the issue where token balances were returned without a corresponding USD value.

Type of change

• New feature (non-breaking change which adds functionality)
• Documentation update

How Has This Been Tested?

• Successfully fetched token prices using Dexscreener for different contract addresses on Base.
• Verified that returned values match the expected price from Dexscreener API.

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• New and existing unit tests pass locally with my changes

Screenshots (if appropriate):