The inline dummy backend reported files safe before the upload response
returned, so the analyzing upload state was never observable. Delay the
safe result off the request thread to expose it for frontend testing.
Add an ENV_OVERRIDE variable so docker-compose can load an
extra env file (e.g. common.e2e) on top of common.local.
This lets the e2e runner enable WOPI_CLIENTS=collabora
without touching the default dev config.
The backend service was hardcoded to use common.local. We
now use ENV_OVERRIDE to select the env file, consistent with
the postgresql config. This enables e2e tests to use their
own common.e2e env file.
Nicolas Clerc