fix: add eslint disable for require() in TypeScript build

Add eslint disable comment to resolve TypeScript build error for require().

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: nirga

packages/instrumentation-langchain/src/instrumentation.ts

@@ -53,6 +53,7 @@ export class LangChainInstrumentation extends InstrumentationBase {
 
   private instrumentCallbackManagerDirectly() {
     try {
+      // eslint-disable-next-line @typescript-eslint/no-var-requires
       const callbackManagerModule = require("@langchain/core/callbacks/manager");
 
       if (callbackManagerModule?.CallbackManager) {