Build an in-memory SeedFixtureCache. Capped at SESSION_ENTRY_CAP
net-new keys to bound memory from a sandbox-authed caller that keeps seeding
fresh IDs. Existing keys are always writable so re-seeds continue to work at
the cap. Raise the cap explicitly for high-volume test runs.
Build an in-memory SeedFixtureCache. Capped at SESSION_ENTRY_CAP net-new keys to bound memory from a sandbox-authed caller that keeps seeding fresh IDs. Existing keys are always writable so re-seeds continue to work at the cap. Raise the cap explicitly for high-volume test runs.