saas: minor adjustments for search

fix: country code validation

fix: charge amount

fix: formatted usage entry

searcher: image/news/bing search (#1176)

saas: new rate limit policy

fix: curl failure should return 4xx if specified explicitly

feat: search return with date (#1173)

fix: readerlm params

fix: beware readerlm capacity drain

fix: do img filtering in node instead of browser

fix: bring back content based respond timing

fix: cache use and edge cases

fix: restrict auto-fill to first page fetch

improve: cache usage and detection of js-required pages

fix: return 10 search results by default

fix: some response could miss meta field (#1165)

fix: track if snapshot html modified by js

behavior change: ditch content based return timing, adopt mutationIdle as default timing

feat: pdf upload and ip check

fix: url check

fix

fix: caching condition

fix: block suspicious requests before sideload

chore: prefer ctx.URL

chore: add comments to clarify

fix: missing url query param

chore: fix search result amount (#1163)

fix: bad snapshot in sideload should not throw directly

feat: leveraging NODE_COMPILE_CACHE (#1162)

fix: several crash cases

feat: md options pass though to turndown

fix: catch jsdom errors

fix: guard invalid domain names

fix: potential fix for firestore grpc connection reset

fix

fix: somehow side-loading chromewebstore would 100% crash the browser

fix: expect failure while loading pdf

fix: potential invalid pdf issue

cleanup: use local project code as much as possible

fix: implement DNT in alt-gen and pdf-extract

restructure: nolonger a firebase application (#1160)