Implement Soroban Contract Dependency Graph

[mijinummi]

🧠 Concept

Visualize Soroban contract dependencies.

⚠️ Problem

Cross-contract relationships are difficult to audit manually.

📁 Implementation Scope

• src/analysis/dependency-graph/

✅ Requirements

• Detect contract interactions
• Generate graph structure

🎯 Acceptance Criteria

• Dependency graph implemented