refactor: remove legacy local client authority

docs/design/overview.md

@@ -12,12 +12,13 @@ That rule shapes the crate split. The runtime can restart, attach, compact, or d
 - `session-store` owns replayable append-only conversation/session logs.
 - `pod-store` owns current Worker metadata keyed by Worker name.
 - `protocol` defines the socket message boundary between clients and Workers.
-- `client` contains reusable one-shot socket/runtime-command mechanics so lower crates do not depend on the product CLI.
+- `standalone` owns the client-side, one-process Standalone host and its dedicated session store. It does not create Runtime Workers, PID/socket catalogs, or Workspace product authority.
+- `client` contains reusable Backend Workspace/Runtime clients plus the shared `Target` boundary. Its normal targets are exactly Standalone and Backend; it is not a subprocess launcher or repository-local product backend.
 - `manifest` resolves Profiles, Manifests, model/provider references, scopes, prompts, and tool permission policy into a runtime contract.
 - `tools` implements built-in tools with bounded output and policy-aware execution.
 - `memory` owns generated memory summary/decision/request records, linting, staging, and audit observations.
 - `workspace-server` is the local Workspace control-plane seam. It can project Tickets, Workers, lifecycle, usage, and orchestration events, but browser/API operations must stay on opaque backend identities instead of raw local paths, sockets, Worker names, or session files.
-- `tui` is a UI over Worker authority; it should not invent durable state.
+- `tui` is a UI over either one in-process Standalone session or Backend Workspace/Runtime Worker authority; it should not invent a local Worker catalog or durable product state.
 
 ## Why these boundaries exist
 

docs/design/standalone-agent-host.md

@@ -29,6 +29,13 @@ worker
 - `shutdown()` は既存 `Method::Shutdown` を送り、controller が active run、SubWorker registry、Workdir session、MachineScope allocation を順に片付けた後の confirmation を待つ。
 - startup error は category のみを公開し、credential、prompt 本文、session metadata、内部 path を error text に含めない。
 
+## CLI / TUI routing
+
+- `yoi` の connection-aware command は `TargetKind::Standalone | Backend` の二択で dispatch する。`--local` と client config の `default_connection = "local"` は Standalone を選ぶ入力であり、旧 LocalBackend を有効化しない。
+- Standalone の通常起動は `StandaloneHost`、restore は専用 `StandaloneStore` の session picker を使う。Workspace Worker list、PID、Unix socket、subprocess は探索しない。
+- `workers`、Backend Worker restore、Workspace panel、Ticket、Objective は Backend authority を要求する。Standalone から repository-local filesystem backend へ fallback しない。
+- `yoi worker` は Runtime や明示的な process-owned integration が使う direct Worker entrypoint として残るが、通常の `yoi` / TUI 起動経路からは呼び出さない。
+
 ## 非目標
 
 - TUI/CLI routing や画面実装