Mintlify CDN serves 130-byte placeholder PNGs for all files in
docs/images/, making every image across the site broken. Images
co-located with MDX files (e.g. features/workflow/) use different
CDN upload paths and render correctly.
This moves all referenced images to co-located directories matching
their MDX files and removes the entire docs/images/ directory.
Also fixes the Slack link placeholder in troubleshooting page.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>