CULT — PHP on ECS Fargate
=========================
php        : 8.4.23
sapi       : apache2handler
hostname   : ip-172-25-206-219.eu-west-1.compute.internal
fargate    : yes
db drivers : none in this base image

--- RDS connectivity ---
target     : rdsmysql-ddf92da19070c70cff347bbcb2.clka4mu6ctr6.eu-west-1.rds.amazonaws.com:3306
result     : TCP connected in 4ms
handshake  : connected, but no MySQL greeting received

This proves the network path and that MySQL is answering.
Authenticated queries need a driver, which comes with the Laravel image.