fix(extension): handle browser error pages gracefully

- Treat chrome error page script failures as transient during injection retries.
- Return safe fallback values for read-only DOM commands when tabs land on browser error pages.
- Improve URL watch handling by checking pending URLs and reporting last seen URL/status on timeout.
- Bump package and extension version to 0.9.6 and add regression coverage for error-page behavior.

extension/src/commands/tabs.ts

@@ -191,13 +191,26 @@ export async function tabsWatchUrl({ pattern, timeout = 30000, tabId } = {}) {
   const tab = tabId ? await chrome.tabs.get(tabId) : await getActiveTab();
   const deadline = Date.now() + timeout;
   const regex = new RegExp(pattern);
+  let lastUrl = tab.url || tab.pendingUrl || "";
+  let lastStatus = tab.status || "unknown";
+
+  const matches = (url) => {
+    regex.lastIndex = 0;
+    return Boolean(url && regex.test(url));
+  };
+  if (matches(lastUrl)) return tabInfo(tab);
+
   while (Date.now() < deadline) {
     const t = await chrome.tabs.get(tab.id);
-    const url = t.url || t.pendingUrl || "";
-    if (regex.test(url)) return tabInfo(t);
+    lastUrl = t.url || t.pendingUrl || "";
+    lastStatus = t.status || "unknown";
+    if (matches(t.pendingUrl || "") || matches(t.url || "")) return tabInfo(t);
+    if ((t.url || "").startsWith("chrome-error://")) {
+      throw new Error(`Tab ${tab.id} is showing an error page while waiting for URL to match '${pattern}'`);
+    }
     await new Promise(r => setTimeout(r, 200));
   }
-  throw new Error(`Tab ${tab.id} URL did not match '${pattern}' within ${timeout}ms`);
+  throw new Error(`Tab ${tab.id} URL did not match '${pattern}' within ${timeout}ms (last URL: '${lastUrl}', status: '${lastStatus}')`);
 }
 
 export async function tabsMute({ tabId }) {