A session could be created from the sidebar but never removed, so the
chat surface accumulated every experiment anyone ever named. Each row
now carries a small delete affordance that only names the key: the
confirmation is the shell's, and it says the turn history goes with
the session before calling the new route. On confirm the chat moves to
the first remaining session — the stream's watcher follows the key —
so nothing keeps streaming a session that no longer exists.
The row had to stop being a single button, since a nested button is
invalid HTML: the select button and the delete button now sit in a
container that owns the hover and active surface.
kosmos
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