fix(blog): restore TOC, list styling, and dynamic OG images

This commit reapplies fixes directly to main after reverting an accidental feature branch merge.

chore(release): bump version to 2.2.6

tests/og-image.test.ts

@@ -1,6 +1,7 @@
 import { describe, it, expect, beforeAll } from 'vitest';
 
-const BASE_URL = process.env.TEST_URL || process.env.NEXT_PUBLIC_BASE_URL || 'http://localhost:3000';
+const BASE_URL =
+  process.env.TEST_URL || process.env.NEXT_PUBLIC_BASE_URL || 'http://localhost:3000';
 
 describe('OG Image Generation', () => {
   const locales = ['de', 'en'];
@@ -18,7 +19,9 @@ describe('OG Image Generation', () => {
           return;
         }
       }
-      console.log(`\n⚠️  KLZ Application not detected at ${BASE_URL}. Skipping integration tests.\n`);
+      console.log(
+        `\n⚠️  KLZ Application not detected at ${BASE_URL}. Skipping integration tests.\n`,
+      );
     } catch (e) {
       isServerUp = false;
     }
@@ -34,7 +37,7 @@ describe('OG Image Generation', () => {
     // Check for PNG signature: 89 50 4E 47 0D 0A 1A 0A
     expect(bytes[0]).toBe(0x89);
     expect(bytes[1]).toBe(0x50);
-    expect(bytes[2]).toBe(0x4E);
+    expect(bytes[2]).toBe(0x4e);
     expect(bytes[3]).toBe(0x47);
 
     // Check that the image is not empty and has a reasonable size
@@ -49,7 +52,9 @@ describe('OG Image Generation', () => {
       await verifyImageResponse(response);
     }, 30000);
 
-    it(`should generate product OG image for ${locale} with slug ${productSlugs[0]}`, async ({ skip }) => {
+    it(`should generate product OG image for ${locale} with slug ${productSlugs[0]}`, async ({
+      skip,
+    }) => {
       if (!isServerUp) skip();
       const url = `${BASE_URL}/${locale}/api/og/product?slug=${productSlugs[0]}`;
       const response = await fetch(url);
@@ -64,11 +69,26 @@ describe('OG Image Generation', () => {
     }, 30000);
   });
 
-  it('should generate blog OG image', async ({ skip }) => {
+  it('should generate static blog overview OG image', async ({ skip }) => {
     if (!isServerUp) skip();
     const url = `${BASE_URL}/de/blog/opengraph-image`;
     const response = await fetch(url);
     await verifyImageResponse(response);
   }, 30000);
-});
 
+  it('should generate dynamic blog post OG image', async ({ skip }) => {
+    if (!isServerUp) skip();
+    // Assuming 'hello-world' or a newly created post slug.
+    // If it 404s, it still tests the routing, though 200 is expected for an actual post.
+    const url = `${BASE_URL}/de/blog/hello-world/opengraph-image`;
+    const response = await fetch(url);
+    // Even if the post "hello-world" doesn't exist and returns 404 in some environments,
+    // we should at least check it doesn't 500. We'll accept 200 or 404 as valid "working" states
+    // vs a 500 compilation/satori error.
+    expect([200, 404]).toContain(response.status);
+
+    if (response.status === 200) {
+      await verifyImageResponse(response);
+    }
+  }, 30000);
+});