fix: restore recently closed tabs with navigation history

[Draly]

Summary

• Use browser.sessions.restore() instead of Tabs.open() when reopening tabs from the "Recently closed tabs" panel (trash icon), so the restored tab preserves its full navigation history (back/forward buttons work).
• Falls back to the previous Tabs.open() behavior when the tab is no longer available in browser sessions (e.g. older than 25 entries).
• Handles branch restoration: tries session restore for each tab individually, with fallback for tabs not found in sessions.

Problem

Currently, clicking a tab in the "Recently closed tabs" sub-panel creates a brand new tab via browser.tabs.create({ url }). This means the restored tab loses its entire navigation history -- the back button doesn't work, unlike Firefox's native "Recently closed tabs" (History menu) which uses browser.sessions.restore().

Solution

Modified the openTabs() function in sub-panel.closed-tabs.vue to:

1. First attempt to find the closed tab in browser.sessions.getRecentlyClosed()
2. If found, restore it via browser.sessions.restore(sessionId) (preserves history)
3. If not found, fall back to the existing Tabs.open() behavior

Limitations

• browser.sessions.getRecentlyClosed() is limited to ~25 entries by default (browser.sessionstore.max_tabs_undo). Tabs beyond this limit will use the fallback.
• browser.sessions.restore() restores the tab at its original position; Sidebery's tab event handlers will then integrate it into the tree.

Test plan

• Open a tab, navigate through several pages (building history), close the tab
• Open the "Recently closed tabs" panel (trash icon) and click the closed tab
• Verify the back button works and navigation history is preserved
• Test with branch restoration (close a parent tab with children, restore via branch button)
• Test fallback: close many tabs (>25) and try restoring an old one -- should still open via URL

[mbnuqw]

Thanks. Currently there are some issues:

• Container is not preserved:

  • Open https://example.com/ in default container
  • Open https://example.com/ in another container
  • Close the tab in another container
  • Close the tab in default container
  • Open RCT sub-panel and restore containered tab
  • Restored tab is wrong (different container, history)

• Restoring branch of tabs leads to multiple active tabs:

  • Open https://example.com/
  • Open child tab https://www.iana.org/help/example-domains ("Learn more" link)
  • Close the branch (right-click on parent tab's close button)
  • Open RCT sub-panel and restore the branch
  • Both tabs marked as active