Weave Net initially had the ability to start a single component at a time with `launch-proxy` and `launch-router`.
This change enables this again via `--proxy=false` despite the merge of the proxy and the router.
Note that by default:
- `launch` passes `--proxy` which enables the proxy and keeps behaviour consistent with `launch` pre-merge,
- `weaver` defaults `--proxy` to `false` which disables the proxy and keeps behaviour consistent with `weaver` pre-merge (as it was `weaveproxy`'s responsibility).