### 🔐 Add safe amount conversion utilities

[El-swaggerito]

Overview
Avoid floating-point precision issues when converting token amounts.

Requirements

• Add utility to convert human-readable amounts into contract-safe integers
• Avoid JavaScript floating-point errors
• Add tests for decimal conversion

Acceptance Criteria

• Amount conversion is precise
• Large and small values are handled safely
• Utility is documented

Labels: security, utilities

[Empyrean-Code]

@Empyrean-Code has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

I’d love to work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Empyrean-Code to this issue.