PDF export broken on dillinger.io - "Could not find Chrome (ver. 142.0.7444.175)"

Bug Description

PDF export on the production site (dillinger.io) is broken.

Steps to Reproduce

1. Go to https://dillinger.io
2. Write any markdown content
3. Click Export As → PDF
4. Navigate to /factory/fetch_pdf

Expected Behavior

PDF should download successfully.

Actual Behavior

Raw error displayed:

Could not find Chrome (ver. 142.0.7444.175). This can occur if either
 1. you did not perform an installation before running the script (e.g. `npx puppeteer browsers install chrome`) or
 2. your cache path is incorrectly configured (which is: /home/sbx_user1051/.cache/puppeteer).

Environment

• Production site: dillinger.io
• The path /home/sbx_user1051/ suggests a sandboxed cloud environment

Suggested Fix

The recent Dockerfile fix (commit 24f352c) adds proper Chromium installation and sets PUPPETEER_EXECUTABLE_PATH. This fix may need to be deployed to production, or the production environment may need Chrome installed separately with proper path configuration.