feat(studio): keyframe system — parser, runtime, timeline UI, design panel, gesture recording (#1311)

* feat(studio): runtime hooks — global time compiler + keyframe runtime

Add the runtime bridge layer: global time compilation (tween % → clip %),
soft reload after mutations, runtime keyframe preview, and keyframe
commit helper.

* feat(studio): runtime hooks — global time compiler + keyframe runtime

Add the runtime bridge layer: global time compilation (tween % → clip %),
soft reload after mutations, runtime keyframe preview, and keyframe
commit helper.

* feat(studio): keyframe cache + commit hooks

Add hooks for keyframe cache population (tween → clip-relative %),
mutation dispatch, keyframe snapping, and audio beat detection.

* feat(studio): timeline UI — dopesheet diamonds + keyboard nav

Add dopesheet strip with diamond keyframe indicators, timeline property
rows, keyboard navigation (J/Shift+J/Delete/K), and feature gate
(STUDIO_KEYFRAMES_ENABLED defaults to false).

* feat(studio): design panel — arc controls + ease curve + stagger

Add arc path controls (curviness slider, auto-rotate), motion path SVG
overlay, ease curve visualization, stagger controls, and expanded
animation card. Includes border-radius editor dependency from #1217.

* feat(studio): gesture recording core

Add gesture recording engine with RAF sampling, modifier key property
mapping (Shift→rotationXY, Alt→rotation, Cmd→opacity),
Ramer-Douglas-Peucker simplification, and ghost trail SVG overlay.

* fix(studio): keyframe drag + recording bug bash

21 fixes: capture GSAP base at drag start, translate:none before
gsap.set, skip reapplyPathOffsets for GSAP elements, clamp recording
seek, _auto flag for 100% keyframes, overlay flash fix, block edits
during recording.

* feat(studio): keyframe integration wiring + docs

Wire App.tsx recording orchestration, TimelineToolbar K/R buttons,
PropertyPanel per-property diamonds, shortcuts panel, toast
notifications, and keyframes guide documentation. All gated on
STUDIO_KEYFRAMES_ENABLED (default false).

packages/studio/src/hooks/useStudioUrlState.ts

@@ -11,7 +11,6 @@ import {
 interface UseStudioUrlStateParams {
   projectId: string | null;
   activeCompPath: string | null;
-  currentTime: number;
   duration: number;
   isPlaying: boolean;
   compositionLoading: boolean;
@@ -57,7 +56,6 @@ function replaceHash(nextHash: string) {
 export function useStudioUrlState({
   projectId,
   activeCompPath,
-  currentTime,
   duration,
   isPlaying,
   compositionLoading,
@@ -72,6 +70,7 @@ export function useStudioUrlState({
   applyDomSelection,
   initialState,
 }: UseStudioUrlStateParams) {
+  const currentTime = usePlayerStore((s) => s.currentTime);
   const hydratedSeekRef = useRef(initialState.currentTime == null);
   const hydratedInitialTimeRef = useRef(initialState.currentTime == null);
   const hydratedSelectionRef = useRef(initialState.selection == null);