Rebrand landing for security practitioners, redesign, drop toolchain

- Reposition Arcline OS as the OS for people who defend infrastructure
- Add Security Stack section (Wazuh, Suricata, ClamAV, OpenSCAP, Falco,
  gitleaks/trufflehog, syft/grype, Lynis) plus compliance-ready callout
- Reframe editions for SOC/blue-team/cloud-security audiences; add Kali
  and Security Onion comparisons; update meta/OG tags for security intent
- Remove the custom Arcline Toolchain (11 Go tools) and all references
- Redesign CSS: tactical near-black + amber palette, HUD details
  (hero grid, terminal caret + sigil, card corner brackets, status dot),
  sharpened nav/buttons, responsive fixups; both dark and light themes

templates/base.html

@@ -5,6 +5,14 @@
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>{{.Title}}</title>
+    <meta name="description" content="Arcline OS is a hardened Debian-based Linux distribution for security practitioners — pre-configured SIEM agent, network IDS, compliance scanning, and zero telemetry.">
+    <meta name="theme-color" content="#f59e0b">
+    <meta property="og:type" content="website">
+    <meta property="og:site_name" content="Arcline Project">
+    <meta property="og:title" content="{{.Title}}">
+    <meta property="og:description" content="A hardened Debian-based Linux OS for people who defend infrastructure — SIEM agent, network IDS, compliance scanning, and zero telemetry, from first boot.">
+    <meta property="og:url" content="https://arclineproject.org/">
+    <meta name="twitter:card" content="summary">
     <link rel="icon" type="image/svg+xml" href="/static/favicon.svg">
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>