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/lib/foundation4/humans.txt

@@ -0,0 +1,8 @@
+/* Foundation was made by ZURB, an interaction design and design strategy firm in Campbell, CA */
+/* zurb.com */
+/* humanstxt.org */
+
+/* SITE */
+  Standards: HTML5, CSS3
+  Components: jQuery, Orbit, Reveal
+  Software: Coda, Textmate, Git