CCDIKSolver: Make `.createHelper()` compatible with generic `SkinnedMesh`. (#24988)
* Update CCDIKSolver.js
`CCDIKSolver.createHelper()` fallbacks to `this.iks` if no MMD
* Update examples/jsm/animation/CCDIKSolver.js
Co-authored-by: Takahiro <[email protected]>
Co-authored-by: Takahiro <[email protected]>