Add Android theme system and fix package naming issues

This commit adds a comprehensive theming system to Android matching iOS, and fixes package declarations throughout the codebase to match directory structure.

Theme System Additions:
- Added 11 themes matching iOS: Default, Teal, Ocean, Forest, Sunset, Monochrome, Lavender, Crimson, Midnight, Desert, Mint
- Created ThemeColors.kt with exact iOS color values for light/dark modes
- Added ThemeManager.kt for dynamic theme switching
- Created Spacing.kt with standardized spacing constants (xs/sm/md/lg/xl)
- Added ThemePickerDialog.kt for theme selection UI
- Integrated theme switching in ProfileScreen.kt
- Updated App.kt to observe ThemeManager for reactive theming

Component Library:
- Added StandardCard.kt and CompactCard.kt for consistent card styling
- Added FormTextField.kt with error/helper text support
- Added FormSection.kt for grouping related form fields
- Added StandardEmptyState.kt for empty state UI

Package Migration:
- Fixed all package declarations to match directory structure (com.example.mycrib.*)
- Updated package declarations in commonMain, androidMain, and iosMain
- Fixed all import statements across entire codebase
- Ensures compilation on both Android and iOS platforms

iOS Theme Rename:
- Renamed "Default" theme to "Teal" in iOS
- Renamed "Bright" theme to "Default" in iOS to make vibrant colors the default

Build Status:
- ✅ Android builds successfully
- ✅ iOS builds successfully

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

composeApp/src/commonMain/kotlin/com/example/mycrib/cache/DataCache.kt

@@ -1,6 +1,6 @@
-package com.mycrib.cache
+package com.example.mycrib.cache
 
-import com.mycrib.shared.models.*
+import com.example.mycrib.models.*
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow