fix(studio): accept razor splits at the canvas clamp boundary (#1340)

packages/studio/src/utils/timelineElementSplit.ts

@@ -5,6 +5,22 @@ export { buildPatchTarget, readFileContent } from "../hooks/timelineEditingHelpe
 /** Minimum distance (seconds) from clip boundaries to allow a split. */
 export const SPLIT_BOUNDARY_EPSILON_S = 0.03;
 
+/**
+ * True when splitTime leaves at least SPLIT_BOUNDARY_EPSILON_S on both sides
+ * of the cut. Inclusive at the epsilon offsets: the timeline canvas clamps
+ * edge clicks to exactly start/end ± epsilon, so the clamped value must pass.
+ */
+export function isSplitTimeWithinBounds(
+  splitTime: number,
+  clipStart: number,
+  clipDuration: number,
+): boolean {
+  return (
+    splitTime >= clipStart + SPLIT_BOUNDARY_EPSILON_S &&
+    splitTime <= clipStart + clipDuration - SPLIT_BOUNDARY_EPSILON_S
+  );
+}
+
 export function canSplitElement(el: TimelineElement): boolean {
   return (
     !el.timelineLocked &&