Prysm v7.1.4 Slashes Validator Memory in Half

Prysm v7.1.4 ships Gloas fork progress, cutting validator memory from ~264 to ~128 bytes, saving ~300–450 MB heap on mainnet. Sync committee replay fix (#16686), missed attestation fix (#16723), monitor indices fix (#16801), crash fix (#16824). No known security issues. Operators may update.