Add sidebar issue 949 regression tests

Cover collapsed navigation tooltips on hover and focus and verify the Transactions item stays active for nested routes. Existing mobile drawer scroll locking remains covered.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: TheChamp

src/components/Sidebar.test.tsx

@@ -276,6 +276,50 @@ describe("Sidebar", () => {
     });
   });
 
+  describe("issue #949 sidebar behavior", () => {
+    beforeEach(() => {
+      localStorage.setItem("sorokit-sidebar-collapsed", "true");
+    });
+
+    it("shows the collapsed navigation tooltip on pointer hover", async () => {
+      render(
+        <Sidebar active="wallet" onNavigate={onNavigate} open={false} onClose={onClose} />,
+      );
+      const transactions = screen.getByRole("button", { name: "Transactions" });
+
+      fireEvent.pointerMove(transactions, { pointerType: "mouse" });
+
+      expect(await screen.findByRole("tooltip")).toHaveTextContent("Transactions");
+    });
+
+    it("shows the collapsed navigation tooltip when focused by keyboard", async () => {
+      render(
+        <Sidebar active="wallet" onNavigate={onNavigate} open={false} onClose={onClose} />,
+      );
+      const transactions = screen.getByRole("button", { name: "Transactions" });
+
+      fireEvent.focus(transactions);
+
+      expect(await screen.findByRole("tooltip")).toHaveTextContent("Transactions");
+      expect(transactions).toHaveAttribute("aria-describedby");
+    });
+
+    it("highlights the Transactions item for a nested transaction route", () => {
+      render(
+        <Sidebar
+          active="/transactions/123"
+          onNavigate={onNavigate}
+          open={false}
+          onClose={onClose}
+        />,
+      );
+
+      const transactions = screen.getByRole("button", { name: "Transactions" });
+      expect(transactions).toHaveAttribute("aria-current", "page");
+      expect(transactions.className).toContain("bg-surface-3");
+    });
+  });
+
   describe("nav semantics and keyboard access (#550)", () => {
     const NAV_ITEMS = [
       "Wallet",