fix .gitignore dir negation so config/ and scripts/ are tracked

config/bitrix-app/settings_extra.php.example

@@ -0,0 +1,40 @@
+<?php
+// Copy to /home/bitrix/www/bitrix/.settings_extra.php
+// Cache -> memcached instance on :11211 with igbinary serializer.
+// Sessions are switched in .settings.php 'session' section (host memcached-sessions-svc note below).
+
+return array(
+    'cache' => array(
+        'value' => array(
+            'type'      => 'memcached',
+            'memcached' => array(
+                'host' => '127.0.0.1',
+                'port' => 11211,
+            ),
+            // igbinary shrinks cache ~50% and is faster; php8.4-igbinary installed.
+            'serializer' => \Memcached::SERIALIZER_IGBINARY, // = 2
+            // Under load only one process regenerates cache, others get stale copy:
+            'use_lock' => true,       // requires Bitrix main >= 24.0.0
+            'sid'      => $_SERVER["DOCUMENT_ROOT"] . "#01",
+        ),
+        'readonly' => false,
+    ),
+);
+
+/* Sessions (put into .settings.php 'session' value section):
+  'session' => array(
+    'value' => array(
+      'mode' => 'separated',
+      'lifetime' => 14400,
+      'handlers' => array(
+        'kernel'  => 'encrypted_cookies',
+        'general' => array(
+          'type' => 'memcache',
+          'host' => '127.0.0.1',
+          'port' => 11212,
+        ),
+      ),
+    ),
+    'readonly' => true,
+  ),
+*/