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/layout/KebabMenu.svelte

@@ -0,0 +1,56 @@
+<!--
+	Thin wrapper around bits-ui's DM. Provides:
+	- A round ⋯ trigger button styled like the rest of the sidebar's hover
+	  affordances (muted, becomes accent on hover/open).
+	- A portal-positioned content container with shadcn-zinc styling.
+	- An `Item` re-export consumers compose into the menu body so we don't
+	  also have to redeclare the item styling at every call site.
+
+	Items are passed as a snippet via `children` so callers can mix the
+	`Item` re-export, separators, or destructive variants freely.
+-->
+<script lang="ts" module>
+	import { DropdownMenu as DM } from 'bits-ui';
+	export const Item = DM.Item;
+	export const Separator = DM.Separator;
+</script>
+
+<script lang="ts">
+	import { MoreHorizontal } from 'lucide-svelte';
+
+	interface Props {
+		/** Tooltip + aria-label for the trigger button. */
+		label?: string;
+		/** Force the trigger visible regardless of hover state. Used when
+		 *  the menu is open so it doesn't disappear underneath a row hover
+		 *  transition while the user is interacting with it. */
+		alwaysVisible?: boolean;
+		children: import('svelte').Snippet;
+	}
+
+	let { label = 'More', alwaysVisible = false, children }: Props = $props();
+	let open = $state(false);
+</script>
+
+<DM.Root bind:open>
+	<DM.Trigger
+		class="rounded p-0.5 text-xs text-muted-foreground transition-opacity hover:bg-accent hover:text-foreground focus:outline-none {open ||
+		alwaysVisible
+			? 'opacity-100'
+			: 'opacity-0 group-hover:opacity-100'}"
+		title={label}
+		aria-label={label}
+		onclick={(e) => e.stopPropagation()}
+	>
+		<MoreHorizontal class="h-3.5 w-3.5" />
+	</DM.Trigger>
+	<DM.Portal>
+		<DM.Content
+			class="z-50 min-w-[180px] overflow-hidden rounded-md border border-border bg-popover p-1 text-popover-foreground shadow-md outline-none"
+			sideOffset={4}
+			align="end"
+		>
+			{@render children()}
+		</DM.Content>
+	</DM.Portal>
+</DM.Root>