refactor: decouple Memory from asyncpg via StorageBackend protocol#3

Draft

Mearman wants to merge 3 commits intomainfrom

refactor/storage-backend-protocol

Commits on Apr 28, 2026

feat(backend): introduce StorageBackend protocol and PostgresBackend
Mearman
committed
refactor(memory): decouple Memory from asyncpg.Pool via StorageBackend
Mearman
committed
fix: add asserted_at support to StorageBackend protocol
Mearman
committed