fix(ui): add safe-area-inset-bottom padding to GfPageTabsComponent

The GfPageTabsComponent uses height: 100svh which overrides the parent
container's padding-bottom. Move the safe-area-inset-bottom from the
global .page class into the tabs component's :host styles so the bottom
navigation floats above the iOS home indicator.

Closes #6878

libs/ui/src/lib/page-tabs/page-tabs.component.scss

@@ -4,6 +4,8 @@
   display: flex;
   flex-direction: column;
   height: calc(100svh - var(--mat-toolbar-standard-height));
+  padding-bottom: env(safe-area-inset-bottom);
+  padding-bottom: constant(safe-area-inset-bottom);
   width: 100%;
 
   @include mat.tabs-overrides(