added on board page

• Saved trails — save important paths, then search, pin, rename, update, preview, or reopen them later (stored only on your device).
• Scroll restore — best-effort return to your last place on a page when jumping or reopening a path.
• Safer overlay — trail UI runs in an isolated extension frame so pages can’t see or interfere with it; faster reopen with warm hibernation.
• Smarter previews — checks whether a page allows embedding before showing a live preview.
• Reliability — more solid open/seed behavior for saved and inherited paths, plus cleaner surface clipping on Firefox/Zen.
• Still local-only — no accounts, analytics, or TabTrail servers. Optional previews may briefly contact the same page URL you already opened.

Just fixed a bug where ui remains open even if user goes to different tab thats it.