fix: add @ts-expect-error for optional peer dependencies and update knip config

- Add @ts-expect-error comments for @mdx-hybrid/core import
- Add @mdx-hybrid/core to knip ignoreDependencies
- Ensures build passes without optional dependencies installed

Author: jp-knj

knip.js

@@ -50,7 +50,7 @@ export default {
 		'packages/integrations/mdx': {
 			entry: [testEntry],
 			// Required but not imported directly
-			ignoreDependencies: ['@types/*'],
+			ignoreDependencies: ['@types/*', '@mdx-hybrid/core'],
 		},
 		'packages/integrations/netlify': {
 			entry: [testEntry],

packages/integrations/mdx/src/mdx-hybrid-processor.ts

@@ -8,6 +8,7 @@ async function ensureInitialized(): Promise<void> {
   if (!initialized) {
     try {
       // Dynamic import of the mdx-hybrid module
+      // @ts-expect-error - This is an optional peer dependency
       mdxHybridModule = await import('@mdx-hybrid/core');
       if (mdxHybridModule.initialize) {
         await mdxHybridModule.initialize();