- Changed the legacy runtime path from 'legacy-runtime.js' to 'index.js'
in runtime configuration.
- Added a new start script (start.js) to check for the existence of the
built TypeScript server entrypoint and import it.
Note: the legacy githubTokensDb migration is not included in this commit.
It's used only in `agents.js` and will be removed in a future commit. We
will directly use credentials repository instead of github tokens repository.
