Ayumi

• Added a settings screen with light, dark, and system theme selectors.
• Added a direct device sensor step counter mode that works without Health Connect.
• Fixed step counter persistence and accuracy issues across device and app restarts.
• Switched Health Connect sync to active calories to exclude BMR and ensure clean midnight resets.
• Added source package linking and math estimation fallbacks for missing distance or calorie data.
• Fixed permission loops and dashboard layout glitches on first-time setup.