fix(app): latch startup store readiness

packages/app/src/hooks/use-latched-boolean.test.tsx

@@ -0,0 +1,22 @@
+/**
+ * @vitest-environment jsdom
+ */
+import { renderHook } from "@testing-library/react";
+import { describe, expect, it } from "vitest";
+import { useLatchedBoolean } from "./use-latched-boolean";
+
+describe("useLatchedBoolean", () => {
+  it("stays true after the input first becomes true", () => {
+    const { result, rerender } = renderHook(({ value }) => useLatchedBoolean(value), {
+      initialProps: { value: false },
+    });
+
+    expect(result.current).toBe(false);
+
+    rerender({ value: true });
+    expect(result.current).toBe(true);
+
+    rerender({ value: false });
+    expect(result.current).toBe(true);
+  });
+});

packages/app/src/hooks/use-latched-boolean.ts

@@ -0,0 +1,13 @@
+import { useEffect, useState } from "react";
+
+export function useLatchedBoolean(value: boolean): boolean {
+  const [hasLatched, setHasLatched] = useState(value);
+
+  useEffect(() => {
+    if (value) {
+      setHasLatched(true);
+    }
+  }, [value]);
+
+  return hasLatched || value;
+}