Count real readers in CDN logs via asset loads, not user-agents

To estimate humans reading a server-rendered page from CloudFront/Amplify access logs, join page GETs to asset requests whose Referer is that page, and count client IPs that fetched a .js file. On a page shared on LinkedIn, this cut 75 browser-UA IPs to 65: the other 10 sent browser user-agents but loaded no assets, and 9 of them had no Referer, which is typical of disguised unfurl bots. Requests to the site root with the note as Referer and no query string give a rough click-through count. In Amplify logs the column headers are literally cs\(Referer) and cs\(User-Agent), with an unmatched backslash, and generate-access-logs rejects ranges over 2 weeks.