chore: remove fully sponsored txns on zkSync

[thechefpenguin]

[!WARNING] Do not merge until the vault balance for fully sponsored transactions has gotten low. This will revert back to transactions with -20% discount instead of the current "FREE" discount.

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PR-Codex overview

The focus of this PR is to update the banner title and translations related to gas payments on zkSync PancakeSwap. Additionally, it refactors the paymaster token configuration for gas discounts.

Detailed summary

• Updated banner title to reflect gas payment options
• Adjusted translations for gas payment messages
• Refactored paymaster token configuration for gas discounts

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