prerender-v0.98.1 — @harperfast/prerender

@harperfast/prerender 0.98.1

PageCheck stores a digest of the observation, not the observation (#234).

• A row is written for nearly every URL the nightly pass probes while changeProbe.serveCheck is enabled (dry run included), and for every serve-time check, and it replicates to every node. The observation, ~1 KB on a product endpoint, was most of each row.
• The row now carries observedDigest: 96 bits of SHA-256 over the observation's UTF-16 code units, 16 characters. A row drops from ~1 KB to ~228 bytes.
• The sweep compares observedDigest with the digest of its own baseline. It skips exactly the rows it skipped before.

Schema: PageCheck.signature is replaced by PageCheck.observedDigest. This is safe whether or not 0.98.0 rows exist: an old row's digest reads as null, so it spares no probe, and it is replaced on its next write. Deploy 0.98.1 rather than 0.98.0.