note: `00001KW76E8EG` depends on `00001KW7726H9`; embedded Runtime fs-store persistence should persist the canonical Runtime Worker creation model rather than an embedded-only bypass. `00001KW7726H9` is currently inprogress, so this Ticket remains queued and must not start a child worktree/Pod until that dependency is merged/validated/closed or an explicit replan changes the dependency.

author: yoi-orchestrator


note: `00001KW7726H9` is now closed after merge/validation, so this Ticket's dependency is resolved. `00001KW7835H0` remains queued and is related to this fs-store migration; run fs-store persistence first before old Pod crate removal.

summary: `00001KW7726H9` が closed になったため、Workspace Backend embedded Runtime を memory-backed から `worker-runtime` fs-store backed に切り替える。Runtime store root は user data 配下の workspace-id 別 local state とし、Browser-facing API には出さない。Backend restart 後に catalog / worker snapshot / transcript / ConfigBundle store が復元され、live execution handle は connected として偽装せず stale/unconnected diagnostic として扱う。

role_plan: Orchestrator が dedicated child worktree を作成し、coder Worker に `crates/workspace-server`, `crates/worker-runtime`, 必要に応じて `crates/worker`, root Cargo/package files の focused write scope を委譲する。reviewer Worker は read-only で fs-store feature enablement、ServerConfig store-root authority、restart restore behavior、ConfigBundle/transcript restore、stale execution diagnostic、Browser-facing non-leak、memory-backed production bypass absence を確認する。merge/validation/done/cleanup は Orchestrator が行う。現時点では `StopPod` は使用せず、cleanup は child worktree/branch のみ行う。