Add pinnable new-tab targets to the tab row and sidebar

Any new-tab target (new agent, terminal, browser, or a terminal profile)
can be pinned as a quick-launch button. Pins are global client app state
(persisted), not daemon config, so the same set shows on every workspace;
profile pins resolve per host and are dropped where that profile is absent.

The sidebar mirror launches via a navigate-then-launch intent store rather
than calling the create handlers directly: terminal creation only works in
the mounted/focused workspace, so the sidebar requests the launch and the
workspace screen consumes it on focus.

packages/app/src/workspace-pins/store.ts

@@ -0,0 +1,25 @@
+import AsyncStorage from "@react-native-async-storage/async-storage";
+import { create } from "zustand";
+import { createJSONStorage, persist } from "zustand/middleware";
+import { isTargetPinned, togglePinnedTarget, type PinnedTabTarget } from "@/workspace-pins/target";
+
+interface PinnedTargetsState {
+  pinned: PinnedTabTarget[];
+  toggle: (target: PinnedTabTarget) => void;
+  isPinned: (target: PinnedTabTarget) => boolean;
+}
+
+export const usePinnedTargetsStore = create<PinnedTargetsState>()(
+  persist(
+    (set, get) => ({
+      pinned: [],
+      toggle: (target) => set((state) => ({ pinned: togglePinnedTarget(state.pinned, target) })),
+      isPinned: (target) => isTargetPinned(get().pinned, target),
+    }),
+    {
+      name: "pinned-tab-targets",
+      storage: createJSONStorage(() => AsyncStorage),
+      partialize: (state) => ({ pinned: state.pinned }),
+    },
+  ),
+);