fix(player): handle Infinity duration; add lint rules for data-duration and Math.ceil overshoot (#243)

* fix(player): handle Infinity duration from runtime gracefully

When compositions have repeating animations without data-duration, the
runtime sends durationInFrames: Infinity. The player now ignores
non-finite duration values instead of displaying "Infinity:NaN" in the
controls. formatTime also returns "0:00" for non-finite inputs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* feat(lint): add data-duration and Math.ceil overshoot rules

- Add root_composition_missing_data_duration warning when the root
  composition element is missing data-duration, which causes the runtime
  to infer Infinity for loop-inflated timelines.
- Add gsap_repeat_ceil_overshoot warning that catches
  repeat: Math.ceil(d/c)-1 patterns which overshoot the intended
  duration. Recommends Math.floor instead.
- Fix gsap_infinite_repeat fixHint to suggest Math.floor (not Math.ceil).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(player): wait for injected runtime before declaring ready

When the player auto-injects the runtime script (because the
composition has GSAP timelines but no runtime), it would immediately
declare ready on the next probe cycle — before the runtime script
finished loading from CDN. This caused play() to send a postMessage
that nobody received, making autoplay silently fail.

Now the probe waits for the runtime bridge (__hf or __player) to
appear before proceeding to the ready state.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/player/src/controls.ts

@@ -20,7 +20,11 @@ export function formatSpeed(speed: number): string {
 }
 
 export function formatTime(seconds: number): string {
-  const s = Math.max(0, Math.floor(seconds));
+  // Handle non-finite values gracefully
+  if (!Number.isFinite(seconds) || seconds < 0) {
+    return "0:00";
+  }
+  const s = Math.floor(seconds);
   const m = Math.floor(s / 60);
   const sec = s % 60;
   return `${m}:${sec.toString().padStart(2, "0")}`;