external-deps-start can crash in case of branch switch

Reproduction steps

Note: I noticed the script crashing from time to time. The steps below are what I think made the script crash, without being 100% sure.

1. Start the script (node ./scripts/external-deps-start.js PATH dev)
2. In PATH, switch to another branch

Expected

The script stops gracefully with a waring, or adapts itself to the new context

Actual

The script crash and leave the cristal repository in an invalid intermediate state.
The servers (vite, realtime, etc) are not stopped and keep running in the backgroud.

Proposed fix

Add a mechanism to catch any error and act as a safety net to be sure everything is cleared correctly.
Optionally, add a mechanism to be "branch-aware" and do more dynamic adaptations.