[FEATURE]: Setting to open new tabs at the top of the vertical tab list

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

With vertical tabs on (Settings → Appearance → Tabs), new session tabs always land at the bottom of the list. Once you've got more than a screen's worth of sessions open, the tab you just created is off screen and you have to scroll down to reach it every time.

I'd like a setting that flips this: newest tab at the top instead of the bottom. Something like a "new tabs open at top/bottom" choice next to the existing vertical/horizontal tab layout setting, defaulting to the current bottom behavior so nothing changes unless you opt in. Drag-and-drop reordering would still work on top of either mode.

Checked and there's no way to do this today through settings or a plugin. Tab state lives entirely in the app's own store and every tab-creation path appends to the end of the array, so this needs a small core change plus a new setting rather than something pluggable.

Start in the tab state store and trace every tab-creation path mentioned in the issue, then inspect the Settings → Appearance → Tabs UI. Add a setting that selects top or bottom insertion while preserving the current bottom default. Done means new tabs appear in the selected position, drag-and-drop reordering still works, and existing behavior is unchanged by default.