crow-memory-sdk — reqwest client for the crow-memory HTTP server.
Same method surface as the old in-process MemoryStore, minus open/path:
MemoryClient::connect(url). Connection failures and 502/503/504 retry
with exponential backoff (v1 lesson: a service blip with no backoff
killed the whole experiment). 4xx and 500 fail fast — 500s from the
store are not retried so non-idempotent writes never double-apply.