Choosing Gotenberg in ./devenv started the `pdf` sidecar and configured
nothing else, so the app still defaulted to dompdf. Pointing it at the
sidecar by hand then hit the SSRF guard, because `pdf` resolves to a
private address on the compose network — the failure #691 fixed, hit
from inside our own dev environment.
The three gotenberg compose files now set PDF_DRIVER, GOTENBERG_HOST and
GOTENBERG_ALLOWED_PRIVATE_HOST on php-fpm, so the stack renders through
the sidecar with no .env editing at all. The serversideup pool config
already sets `clear_env = no`, so these reach the workers; verified by
generating a real invoice PDF end to end (24967 bytes, %PDF-1.4).
Setting the environment in compose rather than writing to .env keeps the
devenv script from mutating a developer's own file — it does not touch
.env today, and the values belong to the compose file the developer
selected. Non-Docker setups have the same keys documented in .env.example.
devenv now prints what it configured, including that the compose file
exempts that one host from the SSRF guard, since a security control being
relaxed should not be silent.
