Meet accessibility and haptic feedback goals

[fbraza]

Summary

Bring the voice-to-text screen up to accessibility and feedback standards.

Requirements

• Add semantic labels and hints to all buttons (pause, stop, replay, navigation tabs).
• Guarantee every interactive element meets the 48x48dp minimum tap target (padding or SizedBox as needed).
• Verify color contrast of primary elements meets WCAG AA; adjust secondary greys if required.
• Enable screen reader announcements for key state changes (for example, recording started/stopped and error states).
• Add subtle haptic feedback on button presses using the appropriate HapticFeedback APIs.

Acceptance Criteria

• Accessibility services (TalkBack/VoiceOver) can identify and activate all controls with descriptive labels.
• Tap targets meet the minimum size without visual regressions.
• Color contrast passes automated or manual checks against the provided palette.
• Buttons trigger haptic feedback on supported devices without breaking platforms that lack it.