Git panel: share checkout actions + fix push loading (#20)

* Update files

* Git panel: share checkout actions

Hoist checkout-scoped async git actions into a shared store and keep primary Push CTA loading in-place. Also stabilize e2e git flows.

* Stabilize git panel async actions and fix e2e flakes

packages/app/src/stores/checkout-git-actions-store.test.ts

@@ -0,0 +1,67 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { useSessionStore } from "@/stores/session-store";
+import {
+  __resetCheckoutGitActionsStoreForTests,
+  useCheckoutGitActionsStore,
+} from "@/stores/checkout-git-actions-store";
+
+function createDeferred<T>() {
+  let resolve!: (value: T) => void;
+  let reject!: (reason?: unknown) => void;
+  const promise = new Promise<T>((res, rej) => {
+    resolve = res;
+    reject = rej;
+  });
+  return { promise, resolve, reject };
+}
+
+describe("checkout-git-actions-store", () => {
+  const serverId = "server-1";
+  const cwd = "/tmp/repo";
+
+  beforeEach(() => {
+    vi.useFakeTimers();
+    __resetCheckoutGitActionsStoreForTests();
+    useSessionStore.setState((state) => ({ ...state, sessions: {} as any }));
+  });
+
+  afterEach(() => {
+    vi.useRealTimers();
+    __resetCheckoutGitActionsStoreForTests();
+    useSessionStore.setState((state) => ({ ...state, sessions: {} as any }));
+  });
+
+  it("shares pending state per checkout and de-dupes in-flight calls", async () => {
+    const deferred = createDeferred<any>();
+    const client = {
+      checkoutCommit: vi.fn(() => deferred.promise),
+    };
+
+    useSessionStore.setState((state) => ({
+      ...state,
+      sessions: {
+        ...(state.sessions as any),
+        [serverId]: { client } as any,
+      },
+    }));
+
+    const store = useCheckoutGitActionsStore.getState();
+
+    const first = store.commit({ serverId, cwd });
+    const second = store.commit({ serverId, cwd });
+
+    expect(client.checkoutCommit).toHaveBeenCalledTimes(1);
+    expect(
+      store.getStatus({ serverId, cwd, actionId: "commit" })
+    ).toBe("pending");
+
+    deferred.resolve({});
+    await Promise.all([first, second]);
+
+    expect(store.getStatus({ serverId, cwd, actionId: "commit" })).toBe("success");
+
+    vi.advanceTimersByTime(1000);
+    expect(store.getStatus({ serverId, cwd, actionId: "commit" })).toBe("idle");
+  });
+});
+