Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Build (npm run build) was run locally and any changes were pushed
• Unit tests (npm test) were run locally and passed
• E2E Tests (npm run test.karma.prod) were run locally and passed
• Prettier (npm run prettier) was run locally and passed

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

In #3259, we typed an error as
type any as a stopgap measure to allow publishes to occur again. This piece
of debt was left for a future day (which is today).

GitHub Issue Number: N/A

What is the new behavior?

this commit introduces proper type guards for the browser-compile
project, removing the stopgap 'any' usage that was introduced in
#3259

Does this introduce a breaking change?

• Yes
• No

Testing

In this branch, navigate to test/browser-compile and:

• npm run build to test production builds
• npm start to smoke test the application

Other information