feat: Phase 1 foundation - core infrastructure and navigation

Clean Architecture structure:
- core/config - Environment configuration
- core/theme - Material 3 theming with FlexColorScheme
- core/error - Typed exception hierarchy
- core/api - Dio HTTP clients with interceptors
- core/auth - Authentication state management
- routing - go_router with shell navigation
- shared/layouts - Adaptive scaffold

Dependencies added:
- flutter_riverpod, riverpod_annotation, riverpod_generator
- freezed, freezed_annotation, json_serializable
- dio, go_router, shared_preferences
- flex_color_scheme, flutter_adaptive_scaffold

Features:
- Responsive navigation (rail on desktop, bottom on mobile)
- Dashboard placeholder with welcome card
- Theme switching infrastructure
- API client ready for Core API and Tatlock API

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pubspec.yaml

@@ -16,7 +16,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 0.1.0+1
+version: 0.2.0+2
 
 environment:
   sdk: ^3.10.4
@@ -31,22 +31,51 @@ dependencies:
   flutter:
     sdk: flutter
 
-  # The following adds the Cupertino Icons font to your application.
-  # Use with the CupertinoIcons class for iOS style icons.
+  # State Management
+  flutter_riverpod: ^2.6.1
+  riverpod_annotation: ^2.6.1
+  hooks_riverpod: ^2.6.1
+  flutter_hooks: ^0.20.5
+
+  # Code Generation Support
+  freezed_annotation: ^2.4.4
+  json_annotation: ^4.9.0
+
+  # Networking
+  dio: ^5.7.0
+
+  # Routing
+  go_router: ^14.6.2
+
+  # Storage
+  shared_preferences: ^2.3.3
+
+  # UI
+  flex_color_scheme: ^8.1.0
+  flutter_adaptive_scaffold: ^0.3.1
+  flutter_markdown: ^0.7.4
+  fl_chart: ^0.69.2
+
+  # Icons
   cupertino_icons: ^1.0.8
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
 
-  # The "flutter_lints" package below contains a set of recommended lints to
-  # encourage good coding practices. The lint set provided by the package is
-  # activated in the `analysis_options.yaml` file located at the root of your
-  # package. See that file for information about deactivating specific lint
-  # rules and activating additional ones.
-  flutter_lints: ^6.0.0
+  # Linting
+  flutter_lints: ^5.0.0
 
-  # For build-time version generation from pubspec.yaml
+  # Code Generation
+  build_runner: ^2.4.13
+  freezed: ^2.5.7
+  json_serializable: ^6.8.0
+  riverpod_generator: ^2.6.3
+
+  # Testing
+  mocktail: ^1.0.4
+
+  # Build tools
   yaml: ^3.1.0
 
 # For information on the generic Dart part of this file, see the