Fix networkidle timeouts and Firefox cookie domain normalization

- Replace networkidle with domcontentloaded + 5s race in goto, click,
  and session_restore — SPAs with persistent connections (LinkedIn,
  Gmail) never reach networkidle
- Normalize .www. cookie domains in Firefox importer — Playwright
  silently drops cookies with .www.example.com domains

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

dist/mcp.js

@@ -437,7 +437,8 @@ server.tool('session_restore', 'Restore a previously saved session state from a
     }
     // Navigate to saved URL
     if (data.url) {
-        await page.goto(data.url, { waitUntil: 'networkidle' });
+        await page.goto(data.url, { waitUntil: 'domcontentloaded' });
+        await Promise.race([page.waitForLoadState('networkidle'), page.waitForTimeout(5000)]).catch(() => { });
     }
     // Restore storage (runs in browser context)
     const local = data.localStorage || {};