Most of that seems oriented at full, manual archival rather than automated (lightweight-ish) text caching for search operations. ArchiveBox (https://github.com/pirate/ArchiveBox) looks promising, although it isn't capturing the "live" browser feed. Readable-Web Proxy (https://github.com/fake-name/ReadableWebProxy) also looks interesting, but seems to be external as well.

Maybe I just need to suck it up and roll my own.