fix(segment): segment in toolbar uses correct contrast

[liamdebeasi]

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)
  • Some docs updates need to be made in the ionic-docs repo, in a separate PR. See the contributing guide for details.
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue URL: resolves #26350

What is the new behavior?

• iOS segments in a toolbar with color will now have the indicator background set to the theme's contrast color. Since the toolbar background and checked segment button text color is set to the base, we need to use the contrast color on the checked segment's indicator background to ensure an appropriate level of contrast.

Does this introduce a breaking change?

main	branch

• Yes
• No

Other information