fix(api): include connections in deploy request body

[marcosleal-prd]

Description:

• Problem: tinybird build correctly deploys Datasources, Pipes, and Connections to the local/branch workspace. tinybird deploy only sends Datasources and Pipes to the cloud; Connections are never added to the multipart form body for /v1/deploy, so they are not deployed to the main workspace.
• Root cause: In src/api/deploy.ts, the FormData is only populated with datasources and pipes. The “Add connections” loop that exists in src/api/build.ts was missing in the deploy path.
• Fix: Add the same “Add connections” loop in deploy.ts (after adding pipes, before the deployment cleanup step), so that resources.connections are appended to the form with data_project:// and ${conn.name}.connection filenames.
• Testing: Tests were added in build.test.ts and deploy.test.ts to ensure that when resources include connections, both build and deploy include them in the request form data and report the correct connectionCount.

[rmorehig]

Thanks for the PR! 🙏