feat: Implement dark mode support across components and UI elements

- Added dark mode styles to TaskStatusDropdown, TaskStatusDropdownDebug, and TaskStatusDropdownSimple components.
- Introduced ThemeProvider and useTheme hook for managing theme state.
- Updated Button, Card, Input, Loading, Navigation, PageContainer, PageHeader, ProjectCalendarWidget, ProjectMap, SearchBar, States, Tooltip, and other UI components to support dark mode.
- Created ThemeToggle component for switching between light and dark modes.
- Enhanced i18n translations for settings related to theme and language preferences.
- Configured Tailwind CSS to support dark mode with class-based toggling.

src/lib/i18n.js

@@ -526,6 +526,16 @@ const translations = {
       createdAt: "Data utworzenia",
       noUsers: "Brak użytkowników",
       system: "System"
+    },
+
+    // Settings
+    settings: {
+      title: "Ustawienia",
+      appearance: "Wygląd",
+      theme: "Motyw",
+      themeDescription: "Wybierz preferowany motyw",
+      language: "Język",
+      languageDescription: "Wybierz preferowany język"
     }
   },
   
@@ -984,6 +994,16 @@ const translations = {
       createdAt: "Created At",
       noUsers: "No users",
       system: "System"
+    },
+
+    // Settings
+    settings: {
+      title: "Settings",
+      appearance: "Appearance",
+      theme: "Theme",
+      themeDescription: "Choose your preferred theme",
+      language: "Language",
+      languageDescription: "Select your preferred language"
     }
   }
 };