Integer Overflow Checks

[Kaylahray]

User Story

As a User,
I want to ensure math errors don't lose my money.

Description

Use explicitly checked arithmetic.

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Files to Create/Edit

contracts/geev-core/src/
└── mutual_aid.rs

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Functional Requirements

• Math: Replace + with checked_add.
• Math: Replace - with checked_sub.

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Suggested Implementation

// THROUGHOUT CODE:

// 1. Identify all math operations on i128.
// 2. Replace 'a + b' with 'a.checked_add(b).unwrap_or_else(|| panic!(...))'.
// 3. Define specific error codes for Overflow.

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Acceptance Criteria

• No raw operators on token amounts.

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Submission Guidelines

• Branch: security/safe-math