Set the `PRISMA_CLIENT_ENGINE_TYPE` env var to use `dataproxy`

[tanberry]

The Prisma Data Proxy requires users to set the env var PRISMA_CLIENT_ENGINE_TYPE to use the value dataproxy.

The value of dataproxy refers to the PDP Data Proxy, and *can be used in the schema (if the schema is for a PDP project) to define the engineType, but we do not recommend defining it in the schema; instead use the env var.

SMEs are Jakub, Daniel, Alberto.

Pages impacted include(they might be others): -- https://www.prisma.io/docs/reference/api-reference/environment-variables-reference#prisma_client_engine_type --https://www.prisma.io/docs/concepts/components/prisma-engines/query-engine#defining-the-query-engine-type-for-prisma-client

[tanberry]

Just getting back to this. Seems the user will need to add a new line in the .env file, for the PRISMA_CLIENT_ENGINE_TYPE environment variable.

[janpio]

The user needs to set an environment variable, using the .env file is one of multiple supported ways to do that. The current Data Proxy documentation for example sets it manually in the command when running prisma generate.