Drizzle Kit dotenv support

[AlexBlokh]

As of now drizzle-kit config will be automatically supplied with .env file via backed in dotenv package.

In the next version kit will consume .env* files based on NODE_ENV and will be compatible with Bun env consumption. Kit will not consume dotenv files when run in Bun, since Bun already does:

we will read the following files automatically (listed in order of increasing precedence)

• .env
• .env.production .env.development .env.test (depending on value of NODE_ENV)
• .env.local

we will support variables expansion:

DB_USER=postgres
DB_PASSWORD=secret
DB_HOST=localhost
DB_PORT=5432
DB_URL=postgres://$DB_USER:$DB_PASSWORD@$DB_HOST:$DB_PORT/$DB_NAME

you will have an ability to provide custom env file or multiple files or tell Drizzle to not consume files automatically
drizzle-kit --env-file=.env.custom
drizzle-kit --env-file=.env.custom --env-file=.env.custom2
drizzle-kit --no-env -> load custom/yourself

UPD 05.11.24:
pending Bun fix, for now we'll use dotenvx for every runtime