## Summary
- add packages/twenty-apps/rollup-engine: a parameterised rollup engine
that ships a default Opportunity → Company
aggregation.
- declare runtime config in package.json (TWENTY_API_KEY, optional
TWENTY_API_BASE_URL, and ROLLUP_ENGINE_CONFIG) so
app configuration lives entirely in Settings → Apps → [App] →
Configuration.
- document the workflow in README.md: deploy via twenty app sync,
populate env vars in the UI, use the Test panel with
a ready JSON payload, and reference troubleshooting tips.
- adjust the function entry point to a named async export and add
fallback logic for blank base URLs, matching the
UI’s env behaviour.
- prune legacy templates and examples so
config/templates/opportunity-to-company.json is the single copy/paste
starting point.
## UI / UX impact
After syncing the app:
- the Configuration screen shows the three env keys with helpful
descriptions (API key, optional base URL, JSON
override),
- the built-in Test your function panel works immediately
- and the default JSON config is available from
config/templates/opportunity-to-company.json for users who need to
customise rollups.
## Testing
- Out-of-the-box deploy to the hosted workspace (Opportunity update) ✓
- “Test your function” with the default config ✓
- Override example: point debugOpportunityCount at a scratch field via
ROLLUP_ENGINE_CONFIG ✓
- Optional: local smoke test (yarn install && yarn smoke) still passes
