Ionic Theme Material Design 3 v2.0.0

This release improves structured inset lists, toolbar and modal spacing, Ionic 9 compatibility coverage, and integration with the iOS 26 theme.

Breaking change

The section-header class for ion-item-group has been renamed:

- <ion-item-group class="header-item-group">
+ <ion-item-group class="item-group-header">

The old class is no longer styled. Update shared markup used with @rdlabo/ionic-theme-ios26 at the same time.

Added structured two-line inset items using direct, unslotted ion-label and ion-note children.
Removed the divider from the final item in an inset group.
Improved icon-only toolbar and back-button sizing, alignment, and title spacing.
Corrected toolbar padding in regular, card, and sheet modals, including safe-area handling.
Added tested demo and screenshot coverage for Ionic 8 and Ionic 9.
Added complete dual-theme setup guidance, including Sass import order, dark mode, and platform-specific transitions.
Reorganized the public documentation around installation, special markup, grouped lists, and migration.

Requires @ionic/core >=8.8.0 <10.
Using the current iOS 26 theme alongside MD3 requires @ionic/core >=8.8.1.
Applications using @ionic/core <8.8.0 should remain on @rdlabo/ionic-theme-md3@1.0.2 or upgrade Ionic.