Which @angular/* package(s) are relevant/releated to the feature request?

animations

Description

Core, Forms and Router packages have established mechanisms to keep track of the payload size and retained symbols in app bundles. This helps monitor the progress and avoid regressions. Animations package currently don't have one and it'd be great to implement those tests.

Here are PRs where those tests were setup for Forms:

• Retained symbols tracking: build(forms): create sample forms app #38044
• Payload size tracking: test(forms): add integration test app to keep track of payload size #41045

We can use those PRs as a pattern for similar tests for the Animations package.