Model + thinking control refinements (components/model-picker.tsx):
- Drop the '·' separator between the two buttons.
- The thinking button shows just the level ('High', 'Max') — same
doctrine as the model button showing just the model name; '—' when
unknown. Pinned in render-stats-bar (label + no-dot assertions).
- The dropdowns now close on any pointerdown outside the control
(the toggle buttons stay inside the container and keep their own
toggling) and on Esc — the intuitive dropdown contract, instead of
the button being the only way out.
Note: file is graph-stream-owned per SCOPE; touching it per the owner's
direct request (same as cd518a4) — flagged for master.