Fixes the session-list plugin metadata hot path by reusing the active workspace-scoped plugin metadata snapshot for manifest model-id normalization and setup CLI backend fallback. Also keeps model-pricing collection on its provided manifest registry and fixes the CI-only hoisted test mock failure.
Validated with targeted plugin/gateway/model-selection tests, CI-shaped gateway startup shard, Testbox `pnpm check:changed`, and green PR CI.
Thanks @rolandrscheel.