feat: PhotoPrism M0 bring-up — compose stack, web client, sidecar, migrate

Replace the legacy mule-image backend with PhotoPrism plus a thin
SvelteKit client and a Node sidecar for endpoints PhotoPrism doesn't
expose (file rename), and add a two-phase migrator (metadata via PUT,
heaps → albums) for the existing Postgres library.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/lib/components/mule/AnimatedMule.svelte

@@ -0,0 +1,99 @@
+<!--
+	Ported pixel-art header from the legacy mule-image React TopBar.
+	- Tiled `desert.png` scrolling right→left under a dusk gradient.
+	- 3×2 sprite-sheet of the mule cycling at 6 frames / 0.6s for a walk.
+	- ASCII "Mulimago" wordmark on a black plate so the mule has company.
+
+	The PNGs live in /static/mule/ so SvelteKit's static handler serves them
+	at /mule/*; the import-via-Vite trick from the React version isn't
+	necessary here.
+-->
+<script lang="ts">
+	const MULIMAGO_ASCII = `▖  ▖  ▜ ▘
+▛▖▞▌▌▌▐ ▌▛▛▌▀▌▛▌█▌
+▌▝ ▌▙▌▐▖▌▌▌▌█▌▙▌▙▖`;
+
+	interface Props {
+		children?: import('svelte').Snippet;
+	}
+	let { children }: Props = $props();
+</script>
+
+<header class="mule-header relative flex h-16 items-center justify-between overflow-hidden border-b border-border px-4">
+	<div class="relative flex items-center gap-3">
+		<div class="mule-sprite h-12 w-14" aria-label="Mulimago" role="img"></div>
+		<pre
+			aria-label="Mulimago"
+			class="rounded bg-black px-2 py-1 font-mono text-[8px] leading-[1.05] text-white"
+			style="letter-spacing: 0;"
+		>{MULIMAGO_ASCII}</pre>
+	</div>
+
+	<div class="relative flex items-center gap-3">
+		{@render children?.()}
+	</div>
+</header>
+
+<style>
+	/*
+	 * Two layers in the background: tiled desert.png on top scrolling
+	 * right→left, dusk-sky gradient underneath. The 200px tile width is
+	 * fixed so the `desert-scroll` keyframe moves by exactly one tile and
+	 * loops seamlessly.
+	 */
+	.mule-header {
+		background-image:
+			url('/mule/desert.png'),
+			linear-gradient(to bottom, #2b3a5c 0%, #6b6b8a 35%, #d68a5c 75%, #f0c188 100%);
+		background-repeat: repeat-x, no-repeat;
+		background-size:
+			200px 100%,
+			100% 100%;
+		background-position: 0 bottom, 0 0;
+		image-rendering: pixelated;
+		animation: desert-scroll 24s linear infinite;
+	}
+
+	/* 3×2 sprite-sheet, 6-frame walk cycle. `steps(1)` makes each keyframe
+	 * snap (no interpolation between frames). */
+	.mule-sprite {
+		background-image: url('/mule/mule-sprites.png');
+		background-size: 300% 200%;
+		background-repeat: no-repeat;
+		image-rendering: pixelated;
+		animation: mule-walk 0.6s steps(1) infinite;
+	}
+
+	@keyframes mule-walk {
+		0% {
+			background-position: 0% 0%;
+		}
+		16.66% {
+			background-position: 50% 0%;
+		}
+		33.33% {
+			background-position: 100% 0%;
+		}
+		50% {
+			background-position: 0% 100%;
+		}
+		66.66% {
+			background-position: 50% 100%;
+		}
+		83.33% {
+			background-position: 100% 100%;
+		}
+		100% {
+			background-position: 0% 0%;
+		}
+	}
+
+	@keyframes desert-scroll {
+		from {
+			background-position-x: 0px, 0px;
+		}
+		to {
+			background-position-x: -200px, 0px;
+		}
+	}
+</style>