Merge sidebar workspaces across all connected hosts (#1538)

* Merge workspaces across all hosts in the sidebar

Replace per-host sidebar sections with a single merged project list.
Projects that exist on multiple hosts (matched by projectKey) are
collapsed into one row. Host identity is surfaced via:

- A status-only footer pill showing online/offline host counts
- Hover cards with a mandatory host row on every workspace entry
- Subtitles showing the host name when a project spans >1 host
- A host filter in the grouping dropdown (not a sidebar switcher)

Order and group-mode stores migrated from per-server to global keys
with zustand persist migrations. New-workspace screen now shows a
merged project list with a host selector combobox.

Key files:
- workspace-structure.ts: merge algorithm by projectKey
- sidebar-view-store.ts / sidebar-order-store.ts: global state
- sidebar-workspace-list.tsx: context-based subtitle injection
- new-workspace-screen.tsx: host selector in footer row

* Add host filtering to the merged sidebar

The sidebar now merges workspaces from every connected host, so a single
global "active host" no longer fits. Host selection becomes explicit per
action via a host chooser, and agent history pages across all hosts at
once. Removes the active-host / active-server-id model and the
all-agents-list hook that fed it.

* Fix rebase fallout: translate archive host error, update stale workspace-key test

archiveWorkspacesOptimistically used a raw "Host is not connected" string
that the i18n completeness test forbids; route it through i18n.t with the
existing hostDisconnected key. The selectors memoization test asserted
un-prefixed workspace keys, but merged-sidebar keys are serverId-prefixed.

* Fix sidebar review fallout

* Address sidebar review followups

* Fix sidebar workspace identity migration

* Address sidebar review followups

* Handle partial host history failures

* Fix merged sidebar project removal and E2E drift

* Restore history routes and project removal shape

* Remove sidebar host context plumbing

* Tighten sidebar status and host filter state

* Keep new workspace project selection host-compatible

* Migrate sidebar view storage

* Streamline host selection flows

* Update all-host history on archive

* Fix empty project sidebar action

Code regression: the main merge dropped the empty-project New workspace child row while keeping the empty project persistence contract. Restore the row using the project host target so the sidebar stays aligned with the no-host-selection model.

* Fix Japanese shortcut translation key

Stale-base integration: main added the Japanese locale after this branch added cycleAgentMode to the English shortcut help map. Merging main exposed the missing ja key in CI typecheck and resources.test.

* Fix Playwright speech teardown race

packages/app/src/navigation/host-runtime-bootstrap.ts

@@ -2,9 +2,9 @@ import type { ActiveWorkspaceSelection } from "@/stores/navigation-active-worksp
 import type { DaemonStartResult } from "@/runtime/daemon-start-service";
 import type { Href } from "expo-router";
 import {
-  buildHostOpenProjectRoute,
   buildHostRootRoute,
   buildHostWorkspaceRoute,
+  buildOpenProjectRoute,
 } from "@/utils/host-routes";
 
 export interface HostRuntimeBootstrapStore {
@@ -174,20 +174,6 @@ export function resolveWorkspaceSelectionStatus(input: {
   return input.hasHydratedWorkspaces ? "missing" : "unknown";
 }
 
-export function resolveHostIndexRoute(input: {
-  serverId: string;
-  workspaceSelection: ActiveWorkspaceSelection | null;
-  workspaceSelectionStatus: WorkspaceSelectionStatus;
-}): Href {
-  if (
-    input.workspaceSelection?.serverId === input.serverId &&
-    shouldRestoreWorkspaceSelection(input)
-  ) {
-    return buildHostWorkspaceRoute(input.serverId, input.workspaceSelection.workspaceId);
-  }
-  return buildHostOpenProjectRoute(input.serverId);
-}
-
 function isIndexPathname(pathname: string) {
   return pathname === "/" || pathname === "";
 }
@@ -244,7 +230,7 @@ function resolveReadyHostStartupRoute(input: ResolveHostStartupRouteInput): Star
 
   const fallbackServerId = input.hosts[0]?.serverId ?? null;
   if (fallbackServerId) {
-    return { kind: "redirect", href: buildHostOpenProjectRoute(fallbackServerId) };
+    return { kind: "redirect", href: buildOpenProjectRoute() };
   }
 
   return { kind: "redirect", href: WELCOME_ROUTE };