Documentation: Aurora DSQL databases

[mnapoli]

A new documentation page for Aurora DSQL, AWS's serverless PostgreSQL-compatible database: docs/environment/database-dsql.mdx.

It covers:

• how Aurora DSQL compares to RDS and Aurora Serverless (no instance, billed per request, multi-AZ, no VPC and no password on Lambda), and when to use it rather than an RDS database;
• creating a database, with Bref Cloud or the AWS CLI;
• the differences with PostgreSQL that matter to an application: conflicts between concurrent transactions, schema changes, limits;
• connecting Laravel applications with the new bref/laravel-dsql package: configuration, Octane, migrations, and handling conflicts with DB::transaction(attempts: …);
• connecting other PHP applications with the AWS PDO connector;
• monitoring.

The Databases page links to it.

Everything Laravel-specific was checked against real clusters: the package's integration tests, and a Laravel application deployed to Lambda (PHP-FPM, Octane, queue worker) on a database created by Bref Cloud.