Routiner 0.3.1 - Alpha

Changes
Moved all styles to a single global stylesheet for easy theming.
Used .env for secrets and app.config.js for Expo config.
Added Firebase Authentication
Added Login Screen (with dummy buttons)

Next Steps
Implement the login/authentication flow (Firebase + Apple/Google/Anonymous).
Build out the main Habit Tracker UI (date selector, progress bar, habit list, detail modal).
Develop the AI-Log screen (prompt input, AI integration, note approval).
Complete the Settings screen (dark mode, premium toggle, language selection).
Add sub-screens for creating and editing habits.

Full Changelog: 0.3.0...0.3.1