docs: site:install with postgres socket

[tomdavidson]

Existing document
https://www.drush.org/13.x/commands/site_install/

What are you attempting to do
I would like to install the site using postgres driver over a local socket. Ideally via the correct --db-url value, but redirecting some yml config is fine too.

I think it should be something along the lines of
--db-url="pgsql://drupal:drupal@/drupal?host=${PGHOST}?port=${PGPORT}
Where PGHOST is the full file path to the dir containing the socket.

I have tried quite a few variations. At times the error message suggest it needs the host defined as in drupal:drupal@localhost/drupal or that drush is still looking at port 5432 when my PGPORT is 5433. I have also tried including unix_socket= similar to the mysql driver. And I have hard coded all the values rather than rely on the env vars too as well as tried to get around the db-url param:

drush --debug -vvv --no-interaction --config=- site:install drupal_cms_installer << EOF
database:
  default:
    database: drupal
    username: drupal
    password: drupal
    host: /home/tom/Projects/dcms/.devbox/virtenv/postgresql/host
    port: 5433
    driver: pgsql

command:
  site:
    install:
      options:
        account-name: admin
        account-pass: drupal
        site-name: 'Your Site Name'
        account-mail: '[email protected]'
        sites-subdir: default
        locale: en
EOF

In what way is the existing documentation unclear or incomplete
For site:install the docs say that it accepts Drupal 10 style db urls but I can not find specs on what D10 db urls are for postgres & sockets.

Note: docs on the sql cmd says it accepts Drupal 6 style db urls rather than D10.

What should the documentation say instead?
Adding an example for postgres and a local socket would suffice. Linking to the Drupal 10 db url specs would be great.