Support Native XLM

[Kaylahray]

User Story

As a User,
I want to use native XLM, not just wrapped tokens.

Description

Ensure the contract handles the Native Token Address correctly.

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Files to Create/Edit

contracts/geev-core/src/
└── lib.rs

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Functional Requirements

• Integration: Use Soroban's native token client.

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Suggested Implementation

// 1. In 'create_giveaway', ensure the 'token' argument can accept the Native Token Contract Address.
// 2. No specific code logic change, but crucial integration test required to verify 'Client::new' works with the native address.

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Acceptance Criteria

• Tested with Native XLM address.

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Submission Guidelines

• Branch: chore/native-support