feat: overhaul home page, add Terms/Privacy, fix docs links, expand footer

- home.php: remove fake testimonials; add one-line install block with
  copy button; add NixPanel vs cPanel comparison table; add stack
  table; rewrite feature descriptions to be Rust-accurate
- terms.php: full Terms of Service (14 sections)
- privacy.php: full Privacy Policy (11 sections, GDPR-aware)
- index.php: add /terms and /privacy routes
- footer.php: expand to 4-column layout with Product, Resources,
  Support columns; add Terms/Privacy/Changelog/GitHub/bug report links
- header.php: point Docs to github.com/NixReaper/nixpanel-docs

public/index.php

@@ -51,6 +51,8 @@ match (true) {
     $method === 'GET' && $uri === '/'                => view('home'),
     $method === 'GET' && $uri === '/pricing'         => view('pricing'),
     $method === 'GET' && $uri === '/install'         => view('install'),
+    $method === 'GET' && $uri === '/terms'           => view('terms'),
+    $method === 'GET' && $uri === '/privacy'         => view('privacy'),
 
     // ── Auth GET pages ────────────────────────────────────────────────────────
     $method === 'GET' && $uri === '/login'           => (function () {