## Description

This adds some more missing example links.

I also wrote another PR for adding a check to make sure that examples are all linked from a source file and have tests: https://github.com/flutter/flutter/pull/130523

## Related Issues
 - https://github.com/flutter/flutter/issues/129956

## Tests
 - Documentation and refactoring only.

Rename Sample classes

* Fix typos

* lowercase animated & opacity

* Undo typo fix

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Co-authored-by: Michael Goderbauer <goderbauer@google.com>