refactor(update): add an UI indicator in frontend

disable OS native pop up menu and fix autoupdate crash on rpm and snap

#50

public/script/autoUpdate.js

@@ -0,0 +1,81 @@
+async function initUpdateUI() {
+  const container = document.getElementById("updateAvailable");
+
+  const hasUpdate = await window.electronAPI.isUpdateAvailable();
+  if (hasUpdate) {
+    setupAndShowUpdateUI();
+  }
+
+  window.electronAPI.onUpdateAvailable((info) => {
+    setupAndShowUpdateUI(info);
+  });
+
+  function setupAndShowUpdateUI(info) {
+    container.style.display = "block";
+
+    const btn = document.getElementById("btn-update");
+    const icon = document.getElementById("update-icon");
+    const title = document.getElementById("update-title");
+    const sub = document.getElementById("update-sub");
+    const progressWrap = document.getElementById("progress-wrap");
+    const progressFill = document.getElementById("progress-fill");
+    const progressPct = document.getElementById("progress-pct");
+    const progressEta = document.getElementById("progress-eta");
+
+    if (info && info.version) {
+      sub.textContent = `A new version (${info.version}) is ready`;
+    }
+
+    if (info && info.environment && info.environment !== "auto") {
+      icon.textContent = "open_in_new";
+
+      if (info.environment === "snap") {
+        sub.textContent = `Version ${info.version} is out. Use the Snap Store or run "snap refresh".`;
+        btn.textContent = "View Release";
+      } else {
+        sub.textContent = `Version ${info.version} is out. Update via your package manager or download it manually.`;
+        btn.textContent = "Download manually";
+      }
+
+      btn.onclick = () => {
+        window.electronAPI.openReleasePage();
+        container.style.display = "none";
+      };
+
+      return;
+    }
+
+    btn.onclick = () => {
+      window.electronAPI.downloadUpdate();
+      btn.disabled = true;
+      btn.textContent = "Downloading...";
+      icon.textContent = "download";
+      title.textContent = "Downloading update";
+      progressWrap.style.display = "flex";
+    };
+
+    window.electronAPI.onDownloadProgress((progress) => {
+      const pct = Math.round(progress.percent);
+      progressFill.style.width = pct + "%";
+      progressPct.textContent = pct + "%";
+
+      const remaining = (progress.total - progress.transferred) / progress.bytesPerSecond;
+      progressEta.textContent =
+        remaining > 0 ? `~${Math.ceil(remaining)}s left` : "almost done";
+    });
+
+    window.electronAPI.onUpdateDownloaded(() => {
+      progressFill.style.width = "100%";
+      progressPct.textContent = "100%";
+      progressEta.textContent = "Done";
+      icon.textContent = "check";
+      title.textContent = "Ready to install";
+      sub.textContent = "Restart to apply the update";
+      btn.textContent = "Restart";
+      btn.disabled = false;
+      btn.onclick = () => window.electronAPI.installUpdate();
+    });
+  }
+}
+
+initUpdateUI();