feat(blog): add /blog/[slug] post page with dynamic rendering

- Create dynamic route for individual blog posts
- Use force-dynamic for request-time publish gating
- Require Node.js runtime for filesystem reads
- Return 404 for drafts, future posts, or invalid slugs
- Render Markdown with react-markdown + remark-gfm
- No raw HTML rendering (safe by default)
- Include consistent typography and styling

Closes: MKT-69

Author: roomote

apps/web-roo-code/src/app/blog/[slug]/page.tsx

@@ -0,0 +1,173 @@
+import type { Metadata } from "next"
+import { notFound } from "next/navigation"
+import Link from "next/link"
+import ReactMarkdown from "react-markdown"
+import remarkGfm from "remark-gfm"
+import { ArrowLeft } from "lucide-react"
+import { SEO } from "@/lib/seo"
+import { ogImageUrl } from "@/lib/og"
+import { getBlogPostBySlug, formatPostDatePt } from "@/lib/blog"
+
+// Force dynamic rendering to evaluate publish gating at request-time
+export const dynamic = "force-dynamic"
+
+// Require Node.js runtime for filesystem reads
+export const runtime = "nodejs"
+
+interface BlogPostPageProps {
+	params: Promise<{ slug: string }>
+}
+
+export async function generateMetadata({ params }: BlogPostPageProps): Promise<Metadata> {
+	const { slug } = await params
+	const post = getBlogPostBySlug(slug)
+
+	if (!post) {
+		return {
+			title: "Post Not Found",
+		}
+	}
+
+	const PATH = `/blog/${post.slug}`
+
+	return {
+		title: post.title,
+		description: post.description,
+		alternates: {
+			canonical: `${SEO.url}${PATH}`,
+		},
+		openGraph: {
+			title: post.title,
+			description: post.description,
+			url: `${SEO.url}${PATH}`,
+			siteName: SEO.name,
+			images: [
+				{
+					url: ogImageUrl(post.title, post.description),
+					width: 1200,
+					height: 630,
+					alt: post.title,
+				},
+			],
+			locale: SEO.locale,
+			type: "article",
+			publishedTime: post.publish_date,
+		},
+		twitter: {
+			card: SEO.twitterCard,
+			title: post.title,
+			description: post.description,
+			images: [ogImageUrl(post.title, post.description)],
+		},
+		keywords: [...SEO.keywords, ...post.tags],
+	}
+}
+
+export default async function BlogPostPage({ params }: BlogPostPageProps) {
+	const { slug } = await params
+	const post = getBlogPostBySlug(slug)
+
+	// Return 404 if post not found or not published
+	if (!post) {
+		notFound()
+	}
+
+	return (
+		<div className="container mx-auto px-4 py-12 sm:px-6 lg:px-8">
+			<article className="mx-auto max-w-3xl">
+				{/* Back link */}
+				<Link
+					href="/blog"
+					className="mb-8 inline-flex items-center text-sm text-muted-foreground hover:text-foreground">
+					<ArrowLeft className="mr-2 size-4" />
+					Back to Blog
+				</Link>
+
+				{/* Post Header */}
+				<header className="mb-8">
+					<h1 className="text-3xl font-bold tracking-tight sm:text-4xl md:text-5xl">{post.title}</h1>
+					<div className="mt-4 flex flex-wrap items-center gap-4 text-sm text-muted-foreground">
+						<time dateTime={post.publish_date}>Posted {formatPostDatePt(post.publish_date)}</time>
+						{post.tags.length > 0 && (
+							<>
+								<span className="text-border">•</span>
+								<div className="flex flex-wrap gap-2">
+									{post.tags.map((tag) => (
+										<span key={tag} className="rounded-full bg-muted px-2 py-0.5 text-xs">
+											{tag}
+										</span>
+									))}
+								</div>
+							</>
+						)}
+					</div>
+				</header>
+
+				{/* Post Content */}
+				<div className="prose prose-lg max-w-none dark:prose-invert">
+					<ReactMarkdown
+						remarkPlugins={[remarkGfm]}
+						components={{
+							// Do not allow raw HTML - all components render safely
+							h1: ({ ...props }) => (
+								<h1 className="text-2xl font-bold tracking-tight sm:text-3xl" {...props} />
+							),
+							h2: ({ ...props }) => <h2 className="mt-10 text-xl font-bold sm:text-2xl" {...props} />,
+							h3: ({ ...props }) => <h3 className="mt-8 text-lg font-semibold" {...props} />,
+							a: ({ ...props }) => (
+								<a
+									className="text-primary hover:underline"
+									target="_blank"
+									rel="noopener noreferrer"
+									{...props}
+								/>
+							),
+							blockquote: ({ ...props }) => (
+								<blockquote
+									className="border-l-4 border-primary/50 pl-4 italic text-muted-foreground"
+									{...props}
+								/>
+							),
+							code: ({ className, children, ...props }) => {
+								// Check if this is an inline code or code block
+								const isInline = !className
+								if (isInline) {
+									return (
+										<code className="rounded bg-muted px-1.5 py-0.5 text-sm font-mono" {...props}>
+											{children}
+										</code>
+									)
+								}
+								return (
+									<code className={className} {...props}>
+										{children}
+									</code>
+								)
+							},
+							pre: ({ ...props }) => (
+								<pre className="overflow-x-auto rounded-lg bg-muted p-4 text-sm font-mono" {...props} />
+							),
+							ul: ({ ...props }) => <ul className="list-disc pl-6" {...props} />,
+							ol: ({ ...props }) => <ol className="list-decimal pl-6" {...props} />,
+							li: ({ ...props }) => <li className="mt-2" {...props} />,
+							p: ({ ...props }) => <p className="mt-4 leading-7" {...props} />,
+							strong: ({ ...props }) => <strong className="font-semibold" {...props} />,
+							hr: ({ ...props }) => <hr className="my-8 border-border" {...props} />,
+						}}>
+						{post.content}
+					</ReactMarkdown>
+				</div>
+
+				{/* Footer */}
+				<footer className="mt-12 border-t border-border pt-8">
+					<Link
+						href="/blog"
+						className="inline-flex items-center text-sm text-muted-foreground hover:text-foreground">
+						<ArrowLeft className="mr-2 size-4" />
+						Back to Blog
+					</Link>
+				</footer>
+			</article>
+		</div>
+	)
+}