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P2. A keyframe is the start of a linear ramp toward the next; `ScreenView` walks them at `time_units` and `boot.gd` advances that in real time, or freezes it with `--time=<seconds>`. `authored/timing.json` holds the ONE constant this needs. HANDOFF Q1 is answered -- linear, 2 units per rendered frame, 1 unit = 1/60 s -- but that conversion was MEASURED off the running game, not read from a file, so it is authored rather than exported and it says so at length. Expressed as units-per-second, because 60 is exact and 0.01666... is a decimal a reader has to recognise. The timeline stops at the last TIMED keyframe and never plays the exit. Every group's final keyframe carries no `t` -- across this export it is a fade-out for 116 of 134 elements, a scale-and-slide exit for 12, and identical for 6 -- so playing into it would mean inventing how long the ramp takes. That duration is the screen transition, it is measured at ~0.4 s, and it is P3's to author with its own evidence. `exit_ramp_seconds` is therefore null on purpose, not missing. `--pose=rest` keeps the P1 behaviour available: since the port's default is now the timeline and the two DISAGREE, renderer-vs-renderer diffing has to be able to ask for the same assumption the reference renderer makes. The interpolation is checked by where it lands: on 8 of the 12 screens the settled timeline is byte-identical to the rest render.
Authored decisions
Everything here is a decision we made, not something the disc said. It is
hand-written, committed, and survives a re-export — unlike export/, which is
regenerated wholesale and must never be hand-edited.
Every entry carries a why. When the RE agent decodes the real answer, delete
the entry and let the exporter emit it; that deletion is the measure of
progress.
See docs/FORMAT.md for the schemas and docs/BLOCKED.md for which HANDOFF
question each placeholder is standing in for.