chore: release v0.4.13-alpha.1

chore: release v0.4.12

chore: release v0.4.11

chore: release v0.4.11-alpha.1

chore: release v0.4.10

chore: release v0.4.9

chore: release v0.4.8

chore: release v0.4.7

fix: guard layoutWidth/Height with HTMLElement instanceof check

offsetWidth/offsetHeight are only defined on HTMLElement (not on
SVGElement, MathMLElement, etc.). Casting unconditionally can yield
undefined-by-runtime even though TypeScript thinks otherwise. Use an
instanceof check and fall back to the bounding rect dimensions when the
element is not an HTMLElement.

Addresses deferred review feedback from PR heygen-com#290.

fix(hdr): address review feedback across stack

- Document groupIntoLayers tie-break (V8 stable sort → DOM order).
- Expand layerCompositor docstring: merge rationale, visibility inclusion.
- Add tests: empty input, negative z-index, stable tie-break at equal z.
- Document getEffectiveZIndex CSS stacking-context limitations.

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