External reactivity traces for conditional dependencies and effectScope

[PerchAnton]

I made a standalone @vue/reactivity example for interaction-check, a JSONL regression runner I maintain. It provides small reviewable traces without a component harness.

A computed value switches between two reactive fields. The traces check that inactive dependencies do not notify, old dependencies stop notifying after a switch, equal computed values do not rerun the effect, and effectScope.stop stops observation while reads still update.

Adapter · Three scenarios · External PR. Tested with @vue/reactivity 3.5.44: 3 scenarios / 13 steps pass locally on macOS, Node 24.19.0.

From that checkout, with Python 3.10+ and Node 24.19.0:

npm --prefix adapters/javascript ci --ignore-scripts --no-audit --no-fund
python interaction_check.py scenarios/vue-reactivity/*.json -- node adapters/javascript/main.mjs vue-reactivity

Would this be useful as an external example for reactivity reproductions? It is limited to stable @vue/reactivity 3.5.44; it does not cover DOM, components, compiler, Vapor or unreleased APIs. This is a Show and tell example, not a bug report or a core API proposal.