Rename to Arx (display name) with a new fortress icon; knowledge base: Who is Arx

Security assistant chat as the front page (Nox-style, WebLLM on device, grounded in the Devseis knowledge base, Run audit from chat); phone check moved to phone.html

v0.3: phone check (iPhone, Android) as the Space front page, catalog 0.3 (74 checks), shared vulnerability rules, real-CVE training data

Catalog, library and synthetic data v0.2: user account type, USB device access, vulnerabilities

Steps 2-3: control library, training data builder and faithfulness check