feat: add videodb media index with Docker stack

- Add videodb PHP/MySQL media collection manager (Blu-ray, DVD, CD)
- Dockerfile: PHP 8.1 + Apache with GD/mysqli/exif extensions
- docker-compose.yml: app on port 6761 + MySQL 8.0 with health checks
- docker-entrypoint.sh: auto-generates config.inc.php from env vars,
  waits for MySQL, initializes DB schema idempotently
- init-db.php: CLI schema installer using app's own prefix_query() logic
- Persistent volumes for DB, cache, and cover images

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

videodb/vendor/symfony/polyfill-intl-normalizer/Resources/stubs/Normalizer.php

@@ -0,0 +1,17 @@
+<?php
+
+class Normalizer extends Symfony\Polyfill\Intl\Normalizer\Normalizer
+{
+    /**
+     * @deprecated since ICU 56 and removed in PHP 8
+     */
+    const NONE = 1;
+    const FORM_D = 2;
+    const FORM_KD = 3;
+    const FORM_C = 4;
+    const FORM_KC = 5;
+    const NFD = 2;
+    const NFKD = 3;
+    const NFC = 4;
+    const NFKC = 5;
+}