Replace v1 with v2 codebase

Full rewrite: swap out the v1 framework (src/, controllers/, views/,
twig/, sass/, skeleton/) for the working v2 codebase from phpproject
(App/, novaconium/, public/).

novaconium/pages/admin/docs/libraries/index.twig

@@ -0,0 +1,30 @@
+{% extends 'admin/docs/_layout/layout.twig' %}
+
+{% block title %}Libraries{% endblock %}
+
+{% block description %}Plain PHP classes under the Lib\ namespace.{% endblock %}
+
+{% block robots %}noindex, nofollow{% endblock %}
+
+{% block docs_content %}
+    <h1>Libraries</h1>
+
+    <p>Plain PHP classes live in <code>App/lib/</code> (or <code>novaconium/lib/</code> for defaults) under the <code>Lib\</code> namespace and are autoloaded automatically — call them from any sidecar:</p>
+
+    <pre><code>use Lib\Mailer;
+
+(new Mailer())-&gt;send($old['name'], $old['email'], $old['message']);</code></pre>
+
+    <h2>Framework-default classes</h2>
+
+    <p><code>novaconium/lib/</code> ships a few ready-to-use classes any sidecar can call, same as a project's own <code>App/lib/</code> classes — override any of them by dropping a same-named file in <code>App/lib/</code>:</p>
+
+    <ul>
+        <li><code>Lib\Mailer</code> — the contact form's mail stand-in (logs to a file instead of an external mail dependency; see its own source for the note on swapping in a real mail call).</li>
+        <li><code>Lib\SpamGuard</code> — self-hosted honeypot + submission-timing spam detection, reusable on any form. See <a href="/admin/docs/sidecars">Sidecars</a>' "Spam prevention" section for the full write-up.</li>
+        <li><code>Lib\FormValidator</code> — a small accumulating required-field/email/length validator, so a form sidecar doesn't hand-roll the same checks and <code>$errors</code> array every time. Also covered in <a href="/admin/docs/sidecars">Sidecars</a>' "Spam prevention" section.</li>
+        <li><code>Lib\Validate</code> — the lower-level validation primitives <code>FormValidator</code> calls into (<code>isEmail()</code>, <code>minLength()</code>/<code>maxLength()</code>, <code>isMatch()</code>, <code>isPhone()</code>, <code>isPostalCode()</code>/<code>isZipCode()</code>) — call these directly from a sidecar when you just need a validated/normalized value back rather than an accumulated field-error. See <a href="/admin/docs/sidecars">Sidecars</a>' "Spam prevention" section.</li>
+        <li><code>Lib\Input</code> — a cleaning accessor for <code>$_POST</code>/<code>$_GET</code> (<code>Input::post()</code>/<code>Input::get()</code>), used by every sidecar instead of the superglobals directly. Defense-in-depth against HTML/script injection, <strong>not</strong> a defense against SQL injection — see <a href="/admin/docs/sidecars">Sidecars</a>' "Form security" section for the full caveat.</li>
+        <li><code>Lib\Csrf</code> — standalone session-token CSRF protection (<code>Csrf::token()</code>/<code>::verify()</code>), called directly from a sidecar rather than through <code>FormValidator</code>. See <a href="/admin/docs/sidecars">Sidecars</a>' "Form security" section.</li>
+    </ul>
+{% endblock %}