flowchart TD
    A[Draft Markdown] --> B[URL Extraction]
    B --> C[Parallel SSRF-Safe Range GETs]
    C --> D{Status Classifier}
    
    D -->|2xx / 3xx| E[Mark Live]
    D -->|4xx| F[Mark Gone]
    D -->|5xx| G[Mark Server Error]
    D -->|Timeout / Fail| H[Mark Dead]
    
    E --> I[URL Cache: 1 hr TTL]
    F --> J[Dead Link Unwrapper]
    G --> J
    H --> J
    
    J --> K{Is Target URL?}
    K -->|Yes| L[Shield & Retain]
    K -->|No| M[Strip Link, Keep Anchor Text]
    
    L --> N[Verified Output]
    M --> N