…riables

Removes all repository and service instantiation from the root middleware. This is a preparatory step for centralizing dependency injection in `server.dart`. The API is temporarily broken by this change.

- Fixes a critical error in `server.dart` where `Endpoint.uri` was called, which is not available in the current `postgres` package version. The `DATABASE_URL` is now parsed manually to create the `Endpoint`.
- Initializes all data repositories (`User`, `UserAppSettings`, `UserContentPreferences`, `AppConfig`) in addition to the existing ones.
- Wraps the main handler with `provider` middleware for all repositories and `Uuid`, making them available for dependency injection throughout the application.

This commit updates `server.dart` to instantiate all application services, such as AuthService and DashboardSummaryService, injecting the necessary repository dependencies.

These services are then provided to the application via the Dart Frog provider middleware, completing the centralized dependency injection setup.

Updates `routes/_middleware.dart` to reflect the new dependency injection architecture. The middleware now consumes the `Uuid` provider from the context to generate a request ID.

The chain is simplified to apply only the essential global middleware: request ID generation, request logging, and error handling.

…ec.yaml

Adds the foundational `DatabaseSeedingService` class. This service will be responsible for all database schema creation and data seeding operations.

Adds the `createTables` method to the `DatabaseSeedingService`. This method defines and executes the SQL `CREATE TABLE IF NOT EXISTS` statements for all application models within a single transaction.

The schema includes primary keys, foreign keys with cascading deletes, and appropriate data types like `JSONB` and `TIMESTAMPTZ`.

- Implements the `seedGlobalFixtureData` method in `DatabaseSeedingService` to populate the database with initial categories, sources, countries, and headlines from the shared fixtures.
- Uses `ON CONFLICT DO NOTHING` to make the seeding process idempotent.
- Fixes the `createTables` method by replacing the problematic `.transaction()` helper with a manual `BEGIN`/`COMMIT`/`ROLLBACK` block for compatibility and robustness.

Adds the `seedInitialAdminAndConfig` method to `DatabaseSeedingService`. This method inserts the default `AppConfig` and the initial admin `User` from the shared fixtures into the database.

The operation is idempotent, using `ON CONFLICT DO NOTHING` to prevent overwriting existing data on subsequent server starts.

Fixes a bug in `DatabaseSeedingService` where the code was incorrectly attempting to access properties on a `User` object as if it were a `Map`. The logic now correctly accesses the `.roles` property and uses the `User` object from the fixture list directly.

Updates the `seedInitialAdminAndConfig` method to create and insert the default `UserAppSettings` and `UserContentPreferences` records for the seeded admin user.

This fixes a bug where the admin user would lack these necessary associated records, ensuring consistency with the user creation logic in `AuthService`.

Updates `server.dart` to instantiate and run the `DatabaseSeedingService` after the database connection is established.

This ensures that tables are created and initial data (global fixtures, admin user, app config) is seeded on every server start. The idempotent nature of the seeding operations makes this process safe and reliable for both development and first-time production deployments.

Enhances the README.md to reflect the new PostgreSQL database requirement.

- Adds PostgreSQL to the prerequisites.
- Adds a new "Configuration" section explaining the `DATABASE_URL` environment variable.
- Updates the "Run the development server" description to remove references to in-memory repositories and mention the new database seeding process.