*
* To use these images:
* 1. gmail-importer needs to fetch attachments and resolve CID references
* 2. Replace cid: URLs with base64 data URLs
* 3. Then the LLM can analyze them
*
* For now, we extract cid: references to show what images exist, and also
* accept base64 data URLs (if gmail-importer resolves them).
*/
function extractMailPieceImages(htmlContent: string): string[] {
const images: string[] = [];
// Look for img tags
const imgRegex = /