feat: add public shared note page with SSR rendering

- (share) layout group with minimal centered layout
- Server-side load function fetches shared note by token
- Read-only page renders markdown, checklists, and images
- Rate limited via IP-based limiter
- Retro parchment styling with "POWERED BY CRUMBS" footer

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/routes/(share)/+layout.svelte

@@ -0,0 +1,7 @@
+<script lang="ts">
+	let { children } = $props();
+</script>
+
+<div class="flex min-h-screen items-center justify-center bg-[var(--bg-base)] text-[var(--text)]">
+	{@render children()}
+</div>

src/routes/(share)/s/[token]/+page.server.ts

@@ -0,0 +1,28 @@
+import { error } from '@sveltejs/kit';
+import type { PageServerLoad } from './$types.js';
+import { getSharedNote } from '$lib/server/shares-service.js';
+import { checkIpRateLimit } from '$lib/server/ip-rate-limit.js';
+import { db } from '$lib/server/db/index.js';
+
+export const load: PageServerLoad = async ({ params, getClientAddress }) => {
+	const ip = getClientAddress();
+	if (!checkIpRateLimit(ip)) {
+		throw error(429, 'Too many requests');
+	}
+
+	const data = getSharedNote(db, params.token);
+	if (!data) {
+		throw error(404, 'This shared note does not exist or has been removed.');
+	}
+
+	return {
+		token: params.token,
+		title: data.title,
+		content: data.content,
+		checklistMode: data.checklistMode,
+		color: data.color,
+		attachments: data.attachments,
+		createdAt: data.createdAt,
+		updatedAt: data.updatedAt
+	};
+};

src/routes/(share)/s/[token]/+page.svelte

@@ -0,0 +1,123 @@
+<script lang="ts">
+	import { NOTE_COLORS } from '$lib/utils/colors.js';
+	import { renderMarkdown } from '$lib/utils/markdown.js';
+	import type { NoteColor, Attachment } from '$lib/types/index.js';
+
+	interface ChecklistItem {
+		text: string;
+		checked: boolean;
+	}
+
+	const { data } = $props();
+
+	const noteColor = data.color as NoteColor;
+	const bgColor = NOTE_COLORS[noteColor]?.bg ?? NOTE_COLORS.default.bg;
+
+	const renderedContent = renderMarkdown(data.content);
+
+	const checklistItems: ChecklistItem[] = data.checklistMode
+		? data.content
+				.split('\n')
+				.filter((l: string) => l.trim())
+				.map((line: string) => ({
+					text: line.replace(/^- \[[ x]\] /, ''),
+					checked: line.startsWith('- [x] ')
+				}))
+		: [];
+
+	const activeChecklistItems = checklistItems.filter((i) => !i.checked);
+	const doneChecklistItems = checklistItems.filter((i) => i.checked);
+	const sortedChecklistItems = [...activeChecklistItems, ...doneChecklistItems];
+
+	const imageAttachments = (data.attachments as Attachment[]).filter((a) =>
+		a.mimeType.startsWith('image/')
+	);
+
+	function formatDate(date: Date | string) {
+		return new Date(date).toLocaleDateString('en-US', {
+			year: 'numeric',
+			month: 'short',
+			day: 'numeric'
+		});
+	}
+</script>
+
+<svelte:head>
+	<title>{data.title || 'Shared Note'} — Crumbs</title>
+	<meta name="description" content={data.content.slice(0, 160)} />
+</svelte:head>
+
+<div class="mx-4 w-full max-w-2xl py-10">
+	<article
+		class="rounded-sm border border-[var(--border-subtle)] shadow-[var(--card-shadow)] overflow-hidden"
+		style="background-color: {bgColor}"
+		data-testid="shared-note"
+	>
+		<div class="px-6 py-5">
+			{#if data.title}
+				<h1 class="mb-4 text-xl font-semibold text-[var(--text)]" data-testid="shared-note-title">
+					{data.title}
+				</h1>
+			{/if}
+
+			{#if data.checklistMode && checklistItems.length > 0}
+				<ul class="space-y-2" data-testid="shared-note-checklist">
+					{#each sortedChecklistItems as item}
+						<li
+							class="flex items-start gap-2 text-sm {item.checked
+								? 'text-[var(--text-muted)] line-through'
+								: 'text-[var(--text)]'}"
+						>
+							<input
+								type="checkbox"
+								checked={item.checked}
+								disabled
+								class="mt-0.5 h-3.5 w-3.5 shrink-0 rounded border-[var(--border-subtle)]"
+							/>
+							<span class="break-words min-w-0">{item.text}</span>
+						</li>
+					{/each}
+				</ul>
+			{:else if data.content}
+				<div
+					class="prose prose-sm max-w-none text-[var(--text)]"
+					data-testid="shared-note-content"
+				>
+					{@html renderedContent}
+				</div>
+			{/if}
+
+			{#if imageAttachments.length > 0}
+				<div class="mt-4 grid grid-cols-2 gap-2" data-testid="shared-note-images">
+					{#each imageAttachments as attachment}
+						<img
+							src="/api/shared/{data.token}/attachment/{attachment.id}"
+							alt={attachment.filename}
+							class="w-full rounded-sm border border-[var(--border-subtle)]"
+							loading="lazy"
+						/>
+					{/each}
+				</div>
+			{/if}
+		</div>
+
+		<div
+			class="flex items-center justify-between border-t border-[var(--border-subtle)] px-6 py-3"
+		>
+			<span class="text-xs text-[var(--text-muted)]">
+				{formatDate(data.updatedAt)}
+			</span>
+		</div>
+	</article>
+
+	<div class="mt-6 text-center">
+		<a
+			href="https://github.com/bretzel-app/crumbs"
+			target="_blank"
+			rel="noopener noreferrer"
+			class="font-['Press_Start_2P'] text-[8px] tracking-wider text-[var(--text-muted)] hover:text-[var(--primary)] transition-colors"
+		>
+			POWERED BY CRUMBS
+		</a>
+	</div>
+</div>