These two maps build `new gl.Map` directly, so they never got useMapInstance's RTL install, and
their bundle entries registered nothing either. The basemap draws each place in its OWN script,
so over the Middle East most labels are Arabic, Persian or Hebrew for EVERY viewer: they were
drawn as disconnected glyphs in the wrong order. installRtlTextPlugin(gl) now runs after the
engine global resolves and before new gl.Map (an entry-time call cannot work once the engine is
injected lazily).
Gate: check:rtl-raw (+ :poison), gospel's check-gospel-rtl-shaping method (pan to Arabia first;
no RTL label on screen is NOT MEASURED; one defineProperty per global for hook + poison) over
cities-internet on both engines and key-cities (Mapbox-only, gated, no leaf: mounted on a
same-origin host page). The shared gate's --leaf argument can replace the cities rows once it
lands; the key-cities host page still needs this one.
Measured: before, cities-internet mapbox 58 RTL labels with the shaper 'unavailable' and maplibre
62 stuck at 'requested', both unshaped; after, shaper 'loaded' on both, and key-cities 56 RTL
labels shaped. Poison: 3/3 rows caught.