v2.4.3 - Form, overlay and accessibility fixes

Patch release. Nothing to change in your code — update and the fixes are in.

• MForm with validationMode="onChange" validates what was just typed; the error no longer lags one keystroke behind, and onChange fires once per change.
• A dismissible MBanner calls onDismiss once and no longer announces itself as the page header.
• MModal, MDrawer, MSheet and the gallery image preview move focus into the dialog, keep Tab inside it and give focus back when they close. With two open, Escape closes only the top one.
• MSelect and MAutocomplete tell screen readers which option is highlighted. MTooltip is announced with its trigger, closes on Escape and stays on screen.
• Built-in labels (Close, Clear input, Next slide...) can be translated through MI18nProvider under mineralui.common.*.
• Animations respect the reduced-motion setting across the framework.