Is there an existing issue for this?

• I have searched the existing issues

Is your feature request related to a problem?

docker-compose.yml files can use DDEV_PRIMARY_URL like this (example from https://github.com/ddev/ddev-minio):

services:
  minio:
      MINIO_SERVER_URL: ${DDEV_PRIMARY_URL}:10101
      MINIO_BROWSER_REDIRECT_URL: ${DDEV_PRIMARY_URL}:9090

which won't work when using different router ports.

Extended variable expansion doesn't work with docker-compose, so we can't remove the port here.

Describe your solution

Introduce DDEV_SCHEME=https, and then use it like this:

services:
  minio:
      MINIO_SERVER_URL: ${DDEV_SCHEME}://${DDEV_PROJECT}.${DDEV_TLD}:10101
      MINIO_BROWSER_REDIRECT_URL: ${DDEV_SCHEME}://${DDEV_PROJECT}.${DDEV_TLD}:9090

Describe alternatives

Introduce DDEV_PRIMARY_URL_WITHOUT_PORT, but it's not flexible enough.

(Or we can add both variables for convenience.)

Additional context

No response