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/templates/elegant/fullsize.tpl

@@ -0,0 +1,48 @@
+{literal}
+<style>
+.fullsize-icon {
+	position: absolute;
+	margin: 0;
+	padding: 0;
+	width: 30px;
+	height: 30px;
+	background: transparent url(/videodb/javascript/fullsize/fullsize-icon.png) no-repeat left top;
+	z-index: 950;
+	cursor: hand, auto;
+}
+</style>
+
+<script language="JavaScript" type="text/javascript">
+Event.observe(document, 'dom:loaded', function() {
+	$$('img.canzoom').each(function(el) {
+		postop	= el.positionedOffset().top + 5; //+ parseInt(el.getStyle('margin-top').slice(0,-2));
+		posleft	= el.positionedOffset().left + 5;
+
+		icon = new Element('div').addClassName('fullsize-icon').setStyle({display: 'none', top: postop+'px', left: posleft+'px'}); // , border: '1px solid red'
+		icon.srcimage = el;
+		document.body.appendChild(icon);
+
+		icon.observe('click', function(e) {
+			zoomClick(this.srcimage, e);
+		});
+
+		el.writeAttribute({href: el.readAttribute('targetimg')});
+		el.icon = icon;
+
+		el.observe('mouseenter', function(e) {
+			this.icon.appear({duration: 0.3});
+		});
+
+		el.observe('mouseleave', function(e) {
+			mouseX = Event.pointerX(e);
+			mouseY = Event.pointerY(e);
+			el = document.elementFromPoint(mouseX, mouseY);
+
+			if (el != this.icon) {
+				this.icon.fade({duration: 0.3});
+			}
+		});
+	});
+});
+</script>
+{/literal}