DOM XSS Taint Flow 2D: Parallel Sink Lanes & Defense Matrix

This is a 2D-native counterpart to the 3D taint-flow flight simulator: instead of flying a single selected payload through 3D space toward one sink at a time, it runs all five real DOM-based XSS sinks — innerHTML, document.write(), eval(), an inline event-handler attribute, and a javascript: href — as five simultaneous horizontal lanes, each gated by the same three toggleable defenses (output encoding, DOMPurify-style sanitization, strict CSP). A live sink×defense coverage matrix above the lanes renders the full boolean truth table at a glance, so the asymmetry between sinks — the reason a single control is never a universal fix — is visible as a diagram, not just discovered one sink-selection at a time.