Revert "feat: serve content files via catch-all route, use content-relative cover images"

This reverts commit 8d582b6ae3.

app/content/[...path]/route.ts

@@ -1,42 +0,0 @@
-import { NextResponse } from 'next/server';
-import { readFileSync, existsSync } from 'node:fs';
-import { join } from 'node:path';
-
-const CONTENT_DIR = join(process.cwd(), 'content');
-
-const MIME_TYPES: Record<string, string> = {
-  '.jpg': 'image/jpeg',
-  '.jpeg': 'image/jpeg',
-  '.png': 'image/png',
-  '.gif': 'image/gif',
-  '.webp': 'image/webp',
-  '.svg': 'image/svg+xml',
-  '.pdf': 'application/pdf',
-  '.txt': 'text/plain',
-  '.md': 'text/plain',
-  '.mdx': 'text/plain',
-};
-
-export async function GET(
-  _request: Request,
-  { params }: { params: Promise<{ path: string[] }> },
-) {
-  const { path } = await params;
-  const decodedPath = decodeURIComponent(path.join('/'));
-  const fullPath = join(CONTENT_DIR, decodedPath);
-
-  if (!fullPath.startsWith(CONTENT_DIR) || !existsSync(fullPath)) {
-    return new NextResponse('Not found', { status: 404 });
-  }
-
-  const ext = '.' + fullPath.split('.').pop()!;
-  const contentType = MIME_TYPES[ext] ?? 'application/octet-stream';
-  const data = readFileSync(fullPath);
-
-  return new NextResponse(data, {
-    headers: {
-      'Content-Type': contentType,
-      'Cache-Control': 'public, max-age=31536000, immutable',
-    },
-  });
-}

content/posts/euler-identity.mdx

@@ -7,7 +7,7 @@ tags:
   - mathematics
   - euler
   - complex-numbers
-coverImage: /content/posts/euler-identity/euler-cover.jpg
+coverImage: /images/euler-cover.jpg
 ---
 
 Euler's identity is widely regarded as the most beautiful equation in all of mathematics:

content/posts/hello-world.mdx

@@ -7,7 +7,7 @@ tags:
   - typescript
   - programming
   - tutorial
-coverImage: /content/posts/hello-world/typescript-cover.jpg
+coverImage: /images/typescript-cover.jpg
 ---
 
 Welcome to this comprehensive TypeScript tutorial! Whether you are migrating a JavaScript project or starting fresh, this guide will walk you through TypeScript's type system from fundamentals to advanced patterns used in production codebases.

content/posts/hybrid-post.mdx

@@ -8,7 +8,7 @@ tags:
   - signal-processing
   - tutorial
 author: James Liu
-coverImage: /content/posts/hybrid-post/fourier-cover.jpg
+coverImage: /images/fourier-cover.jpg
 ---
 
 ## Fourier Analysis: From Mathematical Theory to Python Practice

next.config.ts

@@ -1,7 +1,9 @@
 import type { NextConfig } from 'next'
 
 const nextConfig: NextConfig = {
-  // Trailing slash for clean URLs
+  // Static export — generates out/ directory with plain HTML
+  output: 'export',
+  // Trailing slash for clean static URLs
   trailingSlash: true,
   // Images: unoptimized required for static export
   images: {