Letter grid v3 — Leap
One extruded letter bounds across the flat letter sea in parabolic hops, tumbling a full turn mid-air and landing flat on the next cell of its word.
A single extruded letter LEAPS in 3D arcs across the grid, hopping from one of the word's cells to the next: it springs up along a parabola, tumbles a whole turn in the air, and lands flat again in the same orientation on the next cell — "des bonds de lettre en lettre". The flat sea of letters from v2 still lies on the ground (so it lands ON letters), but only the hero hops.
For this first version the flying glyph is IDENTICAL throughout (the word's first letter); morphing it into each letter it lands on is the next step. Reuses the shared grid/word-path engine (../_grid.js) and the shared extruded-glyph geometry (../_extrude3d.js); everything is a pure function of animation.progression → seamless loop, recording-safe (no orbitControl).
