Star-cruise nav FEEL rework: spread galaxy, no lurch, real zoom-land

The v11/v12 nav passed structural tests but FELT wrong (piled up, lurched every 8 measures, zoom didn't land). Fixed the feel, verified by measurement:

SPREAD + STARS — FIELD scale 0.55->3.5 (~6.4x); closest suns 3->19 units apart (real empty space). Suns render as EMISSIVE glowing stars (self-lit core + additive corona/halo InstancedMesh)

NO 8-MEASURE LURCH — the lurch was a first-order follow spiking on the first frame after each discrete blend update. Replaced with a critically-damped spring (smoothDamp, CAM_SMOOTH=0.7s, dt-driven/deterministic) easing the galaxy…

CONTINUOUS ZOOM-LAND — unified the star-map and surface regions — the transit pose is one lerp in t (0 deep-space .. 1 touchdown) into a SURFACE_POSE that is byte-identical to the landed pose (C0 handoff, no teleport).

• Preserved: fidelity model, band/faces/dancers/shaders/shadows/HUD, drummer-on-fill, front-on landing, teardown.

▶ Play it: Mercury Interrogation — where the harmony organ has the least anywhere to hide https://stellate.app/?genre=bebop&seed=3756&path=694.13834,713.13867,675.13867&xdur=13.122

b0360ae https://github.com/aboard-io/stellate/commit/b0360aececeb45669da845cfefe73db236de7a10