Remove refreshToken navigation side effects and let callers handle redirects

Co-Authored-By: Codex <codex@openai.com>

tests/stores/login.test.js

@@ -261,13 +261,13 @@ describe("loginStore", () => {
       cookieSetter.mockRestore();
     });
 
-    it("redirects to login and re-throws on failure", async () => {
+    it("re-throws on failure without performing navigation", async () => {
       document.cookie = "luciaRefreshToken=old-refresh-token";
       axios.post.mockRejectedValue(new Error("401"));
 
       await expect(store.refreshToken()).rejects.toThrow("401");
 
-      expect(store.$router.push).toHaveBeenCalledWith("/login");
+      expect(store.$router.push).not.toHaveBeenCalled();
     });
   });
 });