Notidea alpha2.0-release1

NotIdea v2.0-alpha1

Migrate many Riverpod-generated providers to the newer API: provider functions now accept Ref and several provider identifiers (e.g., *NotifierProvider -> *Provider) were updated throughout the UI and logic. Adjusted usages to read/watch the new providers and updated some AsyncValue accessors (valueOrNull -> value) where appropriate. Also updated the app router signature to match the new provider ref type. Bumped key dependencies in pubspec.yaml (flutter_riverpod, riverpod_annotation, go_router, google_fonts, image_cropper, share_plus, flutter_secure_storage, flutter_dotenv, etc.) and regenerated artifact files.