feat: challenge registry-driven platform + XVI/XVII imports + admin toggle + domain rename

- Rename repo/domain: attack-defense-platform / attackdefense.imrnes.team (all refs replaced)
- challenge_registry.json: single source of truth (28 challs across gemastik18/xvi/xvii)
- teams.py: registry-driven CHALLENGES, set_challenge_enabled, sync_challenge_runtime
  (apply enable/disable to live teams: build/up or stop/remove + receiver restart)
- compose_gen.py: render per-team compose from canonical per-challenge templates
  (image reuse, per-team ports 30xxx, flag mounts, passwords)
- gen_canonical_composes.py: canonical docker-compose.yml for all services
- import_new_challenges.py: import XVI/XVII services + EOL base image fixes
  (debian:buster→bookworm, node:14→20, python:3.7-slim→3.11)
- receiver: xvi package (10 checkers) + xvii package (12 generic checkers),
  Challenge base reads PASSWORD_<team_port> from env; gen_receiver_main.py
  generates per-team main.py from registry
- main.py: /api/challenges returns full registry; PATCH /api/challenges/<name>
  toggles enabled + applies to live teams
- index.html: 🏗️ Challenge Manager tab (toggle per challenge, grouped by set)
- SLA bonus now dynamic (all enabled challenges, not hardcoded 6)

services/kode-viewer/views/error.hbs

@@ -0,0 +1,27 @@
+<!doctype html>
+<html>
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width, initial-scale=1.0">
+        <title>kode-viewer</title>
+        <script src="https://cdn.tailwindcss.com"></script>
+    </head>
+    <div class="flex flex-col min-h-screen">
+        {{> header}}
+        <main class="flex-1 flex flex-col items-center justify-center text-center">
+          <div class="w-full max-w-md space-y-8">
+            <div>
+              <h2 class="mt-6 text-center text-3xl font-bold tracking-tight text-foreground">Oops</h2>
+            </div>
+            <div>
+              <p class="text-center text-foreground">{{ message }}</p>
+            </div>
+            <div>
+              <a href="/kode" class="rounded-md text-sm w-full bg-blue-500 hover:bg-blue-700 text-white font-bold py-2 px-4 border border-blue-700 rounded">
+                Go back
+              </a>
+            </div>
+          </div>
+        </main>
+    </div>
+</html>