Public web-only release: SvxPortal front-end + auth backend, install templates and INSTALL.md

Stripped from the internal repo: per-box deploy trees, Go services (nodelist/astmeta/proxy/svxdr),
deploy/sync scripts and all secrets. Config templates for nginx, PHP-FPM, Redis and tmpfiles
live in install/ with CHANGEME placeholders.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

auth/admin_config.php

@@ -0,0 +1,40 @@
+<?php
+declare(strict_types=1);
+require __DIR__ . '/lib.php';
+start_session();
+$uuid = $_SESSION['uid'] ?? null;
+if (!is_string($uuid) || $uuid === '') { header('Location: /'); exit; }
+$me = acct_get($uuid);
+$lvl = acct_admin_level($uuid);
+if ($lvl < 2) { header('Location: /'); exit; }
+
+$page_title = 'Admin · Config — SvxPortal';
+require __DIR__ . '/header.php';
+?>
+<div class="container py-4" style="max-width:800px;">
+  <div class="panel">
+    <div class="d-flex justify-content-between align-items-center mb-3">
+      <h5 class="mb-0">Configuration</h5>
+      <div class="d-flex gap-2">
+        <button type="button" class="btn btn-outline-secondary btn-sm" id="btnView">View</button>
+        <button type="button" class="btn btn-warning btn-sm" id="btnEdit">Edit</button>
+      </div>
+    </div>
+    <div id="viewMode">
+      <pre id="cfgView" class="mono" style="font-size:.8rem; white-space:pre-wrap; margin:0; color:var(--fg);"></pre>
+    </div>
+    <div id="editMode" style="display:none;">
+      <textarea class="form-control mono" id="cfgEditor" rows="25" style="font-size:.8rem; resize:vertical;"></textarea>
+      <div class="d-flex gap-2 mt-3">
+        <button type="button" class="btn btn-primary btn-sm" id="btnSave">Save</button>
+        <button type="button" class="btn btn-warning btn-sm" id="btnSaveReload">Save &amp; Reload</button>
+        <button type="button" class="btn btn-outline-secondary btn-sm" id="btnDiscard">Discard</button>
+      </div>
+    </div>
+    <div id="cfgMsg" class="small mt-2" style="display:none;"></div>
+  </div>
+</div>
+<?php
+$extra_scripts = '<script>var ADMIN_LEVEL = ' . $lvl . ';</script><script src="/auth/admin_config.js"></script>';
+require __DIR__ . '/footer.php';
+?>