Initial index.html: Add OpenWRT firewall visualiser UI

Add a new client-side visualiser at public/index.html for parsing OpenWRT /etc/config/firewall and mapping devices to zones.

Provides a full UI (styles + JS) to parse firewall configs into a model of zones, forwardings and rules, map devices/subnets, render a Cytoscape graph (multiple layouts), show zone connectivity matrix, device relationship tests, and a relationship list.

Includes example config and default device mappings, file upload support, and helper utilities for rule evaluation and UI interactions.

The page is entirely front-end (Cytoscape loaded from CDN) and includes responsive styling.

Author: safesploit