feat(motion): choreography engines + two renderer root causes fixed (#543)

The release cuts read as static screen recordings: one 6s cursor glide
that then vanished, a locked-off camera, metronomic flat card fades. And
two renderer defects were silently wrecking every cut:

- @hyperframes/producer floated (^0.7.36, no lockfile — image builds get
  whatever is latest): 0.7.60 fails EVERY render with "Cannot access 'rt'
  before initialization". Pinned 0.7.36 exact and committed
  package-lock.json so sidecar builds are reproducible.
- the producer's per-clip visibility scheduler runs on a clock that lags
  ~50% behind the encoded timeline on a 40s cut — the final frame showed
  the authored ~18s state, so the tail scenes (bell card, toast, outro)
  were silently missing from the MP4. This, not authoring, is why
  rendered cuts kept losing their late scenes. Fix: clip windows are for
  structural layers only (hero, panel frame, status); every beat rides
  base-hidden styles + delayed CSS animations, which run on the true
  clock. Verified frame-by-frame: all four cards, stats, toast, and
  outro now land exactly on schedule in both cuts.

Craft, made reusable in the kit instead of per-composition heroics:

- kit.js choreographCursor: data-waypoints="t x y [click]; ..." generates
  a multi-leg eased path with fade in/out, an idle-hand sway, and click
  rings + glyph press dips — the cursor behaves like a hand, never pops
  in, freezes, or blinks out
- kit.js choreographCamera: data-shots="t x y scale; ..." — push-ins
  toward each beat's focal point, pull-backs for reveals, settle to end
- release-0.25.0 both cuts re-choreographed: the cursor is the CEO's
  hand (settle on the intake while it types, ONE submit click, witness
  each card completing, acknowledge the toast, exit off-frame); the
  camera lives on every beat; springy card entrances replace flat fades
- motion/README.md gains 'Cinematography & rhythm' (shot-list-first, no
  locked-off camera, verify motion with frame PAIRS) + the clip-window
  rule; kit/README.md documents both engines; the dev video prompt block
  carries the craft bar

Verified end to end through the real sidecar: both cuts render green,
32-frame strips read visually — cursor travels and clicks on schedule,
camera moves, every scene present. motion pnpm test 15/15.

Co-authored-by: Renn F <rennf93@users.noreply.github.com>

motion/kit/README.md

@@ -18,7 +18,8 @@ Every class is namespaced `pk-`. See `compositions/panel-demo/` for a full worke
 - **`pk-pill`** — a status pill: `<span class="pk-pill pk-pill--progress">in progress</span>`. Variants: `--progress`, `--review`, `--approved`, `--completed`. To swap one pill for another (e.g. progress -> completed), stack two pills at the same spot inside a `position: relative` `pk-card__status` and give the outgoing one `pk-pill--swap-out` (fades in then out) and the incoming one `pk-pill--swap-in` (fades in and stays), each with its own `--pk-pill-enter-delay` / `--pk-pill-exit-delay` (composition-absolute seconds — the same convention `data-start` uses).
 - **`pk-toast`** — a notification card that slides in from a corner: `pk-toast__icon` + `pk-toast__body` (`pk-toast__title`, `pk-toast__text`). Position via `--pk-toast-bottom` (right-anchored).
 - **`pk-type`** / **`pk-caret`** — character-by-character typing reveal. Write the target element's final text directly in the HTML, then call `window.PanelKit.typeText(el, { delay, stagger })` (from `kit.js`) once, synchronously, before rendering starts — it splits the text into `pk-type__char` spans with staggered `animation-delay`s (works with any font, no per-character width math). `delay` is the composition-absolute second the first character appears; `stagger` defaults to 0.045s/char. Add a `<span class="pk-caret"></span>` next to it for the blinking caret.
-- **`pk-cursor`** — a small CSS-shape cursor (`pk-cursor__glyph`) that glides along a straight path and pulses (`pk-cursor__ring`) on arrival. Position via `--pk-cursor-x0/y0/x1/y1` (content-box-relative pixels) and timing via `--pk-cursor-delay` (glide start) / `--pk-click-delay` (pulse start), all composition-absolute seconds.
+- **`pk-cursor`** — a small CSS-shape cursor (`pk-cursor__glyph`). Preferred: give it `data-waypoints="t x y [click]; t x y; ..."` (composition-absolute seconds, content-box px) and call `PanelKit.choreographAllCursors()` in the composition's inline script — kit.js generates a multi-leg eased path, a fade-in/out (never pop in or blink out), an idle-hand sway between legs, and a click ring + glyph press dip at every waypoint flagged `click`. The click should land ~0.2s BEFORE the thing it visually triggers. Legacy single-glide via `--pk-cursor-x0/y0/x1/y1` + `--pk-cursor-delay`/`--pk-click-delay` still works for a one-move cameo.
+- **`pk-camera`** — a full-stage wrapper driven by `data-shots="t x y scale; ..."` + `PanelKit.choreographAllCameras()`: eased camera moves (push-ins toward the beat's focal point, pull-backs for reveals). Wrap the whole `pk-frame` in one; everything inside, cursor included, rides the move. Keep it subtle — `scale <= 1.08`, translate <= ~160px — and end settled at identity.
 
 ## Offline constraints (same as every composition)