remove effect

- from a node
- and if there is no node using it, delete it from effect list

Start by scanning the TypeScript source for the node lifecycle code and for the shared structure that stores active effects. Locate where node deletion is handled and where effects are added/removed, then adjust the cleanup flow so an effect is only kept while at least one node still references it. Then run the project’s test/build command from package scripts (or at least a full build/lint) and verify that removing a node no longer leaves orphaned effects in the list.

索引モデルが issue の本文から書いたものです。