v1.2.0 — the whale finally swims forward

The real backwards-swim cause, found by pixel audit: the sprite library had mixed facings — 11 of 14 sheets face LEFT, 3 face RIGHT — so no mirror convention could look right. All sprites are now normalized to the reference whale's left-facing identity; the aquarium recomputes mirror and pitch for that base; the corner companion stays consistent across states.

Also: the speech bubble moved out of the mirrored container (its text was rendering reversed when swimming left), swimming gains true arced turns (steering-based heading), a light UI now gets a sunlit shallow-water palette instead of a dark film, and the scene reads as a glass tank — edge highlight, corner speculars, themed caustics, mono dive badge.