`tinybird deploy --dry-run` should show a detailed diff of changes

[gnzjgo]

Description

Currently tinybird deploy --dry-run only validates the build but doesn't show what resources would be created, modified, or deleted.

The Tinybird dashboard shows a detailed diff when deploying (datasources/pipes created, changed, deleted). The CLI should provide similar information.

Expected behavior

tinybird deploy --dry-run should output a summary like:

Changes to deploy:
  + my_new_datasource.datasource  (create)
  ~ my_pipe.pipe                  (modify)
  - old_datasource.datasource     (delete)