Speed up Instagram extraction + auto-copy checked by default

- Reduce Playwright wait from 10s to early-exit (max 5s)
- Set subtitle auto-copy checkbox checked by default

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

main.py

@@ -463,7 +463,11 @@ def _extract_ig_video_url(url):
 
             page.on('response', _on_resp)
             page.goto(url, wait_until='domcontentloaded', timeout=30000)
-            page.wait_for_timeout(10000)
+            # Wait up to 5s, exit early if video URL found
+            for _ in range(10):
+                page.wait_for_timeout(500)
+                if video_urls:
+                    break
 
             page_title = page.evaluate("""() => {
                 const d = document.querySelector('meta[property="og:description"]');

static/index.html

@@ -1162,7 +1162,7 @@
 
                         <div class="option-group" style="gap: 16px;">
                             <label class="checkbox-wrapper">
-                                <input type="checkbox" id="autoCopy">
+                                <input type="checkbox" id="autoCopy" checked>
                                 <span class="checkbox-custom"></span>
                                 <span>Subtitle Auto Copy</span>
                             </label>