feat: add theme provider and control components for light/dark mode

- Implemented ThemeProvider to manage theme state and preferences.
- Added ThemeControl component for users to switch between system, light, and dark themes.
- Integrated localStorage for theme preference persistence.
- Updated document styles based on theme changes.

test: add tests for permanent deletion of habits and related records

- Created tests to ensure permanent deletion of habits removes all dependent records.
- Verified that deletion requires ownership, authentication, and checks for archived habits.
- Added tests to confirm rollback behavior on deletion failures.

test: add tests for habit palette and progress card functionality

- Implemented tests for habit color progression and theme-based color shading.
- Added tests for progress card calculations and calendar display logic.

feat: define theme types and preferences

- Introduced Theme and ThemePreference types for better type safety.
- Created utility functions for resolving theme based on user preference and system settings.
- Defined theme palettes for light and dark modes to ensure adequate contrast.

src/App.tsx

@@ -3,9 +3,11 @@ import { DesignSystem } from "./pages/DesignSystem";
 import { Home } from "./pages/Home";
 import { AuthProvider } from "./components/AuthProvider";
 
+import { ThemeProvider } from "./components/ThemeProvider";
+
 export function App() {
   return (
-    <Routes>
+    <ThemeProvider><Routes>
       <Route path="/design-system" element={<DesignSystem />} />
       <Route
         path="/"
@@ -16,6 +18,6 @@ export function App() {
         }
       />
       <Route path="*" element={<Navigate to="/" replace />} />
-    </Routes>
+    </Routes></ThemeProvider>
   );
 }