add optional cloudflare web analytics and suppress keep-alive pings from access logs

re-review security report (index model, /tax, curl_cffi, CI secret); move to docs/

move HF Space config out of README into a sync-to-huggingface workflow

raise test coverage to 100% (152 tests)

serve pairs from per-city index (numbeo rankings): 361 cities, up to 10/country, all 92 capitals; myanmar->yangon

expand numbeo cache to all-capital pairs via per-city index

serve cross-country comparisons from an offline numbeo cache

switch numbeo scraper to curl_cffi with chrome tls impersonation

harden numbeo fetch with browser headers, cookie priming and retry

split dense README into docs/ (architecture, testing, deployment)