feat(frontend): select photo in album grid and show info in panel

- single click selects a photo (ring + aria-pressed) and shows its info in the right panel without navigating; double click opens the viewer
- shared 'selection' store; panel uses the route photo in viewer mode and the selected photo in album mode; selection resets on album change
- openspec: sync lightroom-workspace-ui (grid-selection requirement, viewer chrome wording without timers, nested f fullscreen, tasks 9.9/9.10)

frontend/src/lib/components/AlbumPanel.svelte

@@ -8,6 +8,7 @@
 	import PhotoInfoSettingsDialog from './PhotoInfoSettingsDialog.svelte';
 	import { albums } from '$lib/stores/albums.svelte';
 	import { auth } from '$lib/stores/auth.svelte';
+	import { selection } from '$lib/stores/selection.svelte';
 	import { buildExifRows, EXIF_BASE, EXIF_CATALOG, EXIF_LABELS } from '$lib/exif';
 	import type { Album, Photo, Preferences } from '$lib/types';
 
@@ -25,10 +26,15 @@
 	let savingName = $state(false);
 	let nameError = $state('');
 
-	const canEdit = $derived(role === 'owner' || role === 'admin');
-	const canRename = $derived(!!photo && (canEdit || photo.uploader_id === auth.user?.id));
+	const selectedPhoto = $derived(selection.albumId === albumId ? selection.photo : null);
+	const panelPhoto = $derived(photoId ? photo : selectedPhoto);
 
-	const exif = $derived((photo?.exif ?? {}) as Record<string, unknown>);
+	const canEdit = $derived(role === 'owner' || role === 'admin');
+	const canRename = $derived(
+		!!panelPhoto && (canEdit || panelPhoto.uploader_id === auth.user?.id)
+	);
+
+	const exif = $derived((panelPhoto?.exif ?? {}) as Record<string, unknown>);
 
 	const prefs = $derived(auth.preferences);
 	const labelOverrides = $derived(prefs.photo_info?.labels ?? {});
@@ -97,24 +103,33 @@
 			.catch((e) => (error = (e as Error).message));
 	});
 
+	$effect(() => {
+		// сброс временного состояния панели при выборе другого фото в сетке
+		selectedPhoto?.id;
+		editingName = false;
+		nameError = '';
+		showAll = false;
+	});
+
 	function startEdit() {
-		if (!photo) return;
-		nameDraft = photo.original_filename;
+		if (!panelPhoto) return;
+		nameDraft = panelPhoto.original_filename;
 		nameError = '';
 		editingName = true;
 	}
 
 	async function saveName(ev: Event) {
 		ev.preventDefault();
-		if (!photo || !nameDraft.trim()) return;
+		if (!panelPhoto || !nameDraft.trim()) return;
 		savingName = true;
 		nameError = '';
 		try {
-			const data = await api<{ photo: Photo }>(`/photos/${photo.id}`, {
+			const data = await api<{ photo: Photo }>(`/photos/${panelPhoto.id}`, {
 				method: 'PATCH',
 				body: { original_filename: nameDraft.trim() }
 			});
 			photo = data.photo;
+			if (selectedPhoto?.id === data.photo.id) selection.select(albumId, data.photo);
 			editingName = false;
 		} catch (e) {
 			nameError = (e as Error).message;
@@ -154,8 +169,8 @@
 	const metaRow = 'text-text-muted flex justify-between gap-2 py-0.5 text-xs';
 </script>
 
-{#if photoId}
-	{#if photo}
+{#if panelPhoto}
+		{@const p = panelPhoto}
 		<div>
 			<div class="p-4">
 				{#if editingName}
@@ -195,10 +210,10 @@
 						title="Переименовать"
 						onclick={startEdit}
 					>
-						{photo.original_filename}
+						{p.original_filename}
 					</button>
 				{:else}
-					<h2 class="text-text truncate text-sm font-semibold">{photo.original_filename}</h2>
+					<h2 class="text-text truncate text-sm font-semibold">{p.original_filename}</h2>
 				{/if}
 			</div>
 
@@ -218,12 +233,12 @@
 					</button>
 				{/snippet}
 				<dl class="space-y-1">
-					<div class={metaRow}><span>Автор</span><span class="text-text">{photo.uploader.name}</span></div>
-					<div class={metaRow}><span>Файл</span><span class="text-text">{formatSize(photo.size)}</span></div>
-					<div class={metaRow}><span>Тип</span><span class="text-text">{photo.mime_type}</span></div>
+					<div class={metaRow}><span>Автор</span><span class="text-text">{p.uploader.name}</span></div>
+					<div class={metaRow}><span>Файл</span><span class="text-text">{formatSize(p.size)}</span></div>
+					<div class={metaRow}><span>Тип</span><span class="text-text">{p.mime_type}</span></div>
 					<div class={metaRow}>
 						<span>Разрешение</span>
-						<span class="text-text">{photo.width}×{photo.height}</span>
+						<span class="text-text">{p.width}×{p.height}</span>
 					</div>
 					{#each showAll ? allExifRows : visibleExifRows as row (row.key)}
 						<div class={metaRow}>
@@ -242,27 +257,27 @@
 							…
 						</button>
 					{/if}
-					{#if photo.taken_at}
+					{#if p.taken_at}
 						<div class={metaRow}>
 							<span>Снято</span>
-							<span class="text-text">{new Date(photo.taken_at).toLocaleString()}</span>
+							<span class="text-text">{new Date(p.taken_at).toLocaleString()}</span>
 						</div>
 					{/if}
-					{#if photo.latitude != null && photo.longitude != null}
+					{#if p.latitude != null && p.longitude != null}
 						<div class={metaRow}>
 							<span>Координаты</span>
-							<span class="text-text">{photo.latitude.toFixed(5)}, {photo.longitude.toFixed(5)}</span>
+							<span class="text-text">{p.latitude.toFixed(5)}, {p.longitude.toFixed(5)}</span>
 						</div>
 					{/if}
 					<div class={metaRow}>
 						<span>Загружено</span>
-						<span class="text-text">{new Date(photo.created_at).toLocaleString()}</span>
+						<span class="text-text">{new Date(p.created_at).toLocaleString()}</span>
 					</div>
 				</dl>
 			</PanelSection>
 
 			<PanelSection id="photo-comments" title="Комментарии">
-				<Comments photoId={photo.id} />
+				<Comments photoId={p.id} />
 			</PanelSection>
 		</div>
 
@@ -278,8 +293,7 @@
 				onClose={() => (settingsOpen = false)}
 			/>
 		{/if}
-	{/if}
-{:else if album}
+{:else if album && !photoId}
 	<div>
 		<PanelSection id="album-cover" title="Обложка">
 			<div class="bg-bg-muted border-border aspect-video overflow-hidden rounded-lg border">

frontend/src/lib/components/PhotoGrid.svelte

@@ -5,10 +5,12 @@
 
 	interface Props {
 		photos: Photo[];
+		selectedId?: string | null;
+		onSelect?: (index: number) => void;
 		onOpen?: (index: number) => void;
 	}
 
-	let { photos, onOpen }: Props = $props();
+	let { photos, selectedId = null, onSelect, onOpen }: Props = $props();
 </script>
 
 {#if photos.length === 0}
@@ -22,8 +24,13 @@
 			<li>
 				<button
 					type="button"
-					class="border-border bg-bg-muted group relative block aspect-square w-full overflow-hidden rounded-lg border"
-					onclick={() => onOpen?.(i)}
+					class="border-border bg-bg-muted group relative block aspect-square w-full overflow-hidden rounded-lg border {photo.id ===
+					selectedId
+						? 'ring-primary ring-2'
+						: ''}"
+					aria-pressed={photo.id === selectedId}
+					onclick={() => onSelect?.(i)}
+					ondblclick={() => onOpen?.(i)}
 				>
 					{#if photo.thumb_url}
 						<img