Implement Soroban Source Mapping Engine

[mijinummi]

🧠 Concept

Map findings directly to source locations.

⚠️ Problem

Developers struggle to locate affected code quickly.

📁 Implementation Scope

• src/mapping/stellar/source-maps/

✅ Requirements

• Resolve source locations
• Track line and column information
• Link findings to code

🎯 Acceptance Criteria

• Source mapping implemented
• Findings linked accurately