Relax a bit moveChecks to account for shared nodes

Closes #455

See merge request !398

Also, remove caddy from docker-compose.

This commit fixes a bug where a user member of a team (but NOT the owner
of such team) couldn't move nodes.

No need to copy .nix files. They are bound by CI anyways.

Also, graphviz and igraph are in separate nix files now.

The problem was caused by the improper usage of
`delegate_ctrl` when creating the coreNLP process. For a long
time I was under the impression this flag was essential to allow child
processes to shutdown cleanly without leaving zombie threads, but the
result here in the context of the testsuite was that the coreNLP server
was receiving the first Ctrl^C, completely starving the Haskell RTS,
which wouldn't receive any and as a result our testsuite would be
running forever.

By default, we shouldn't run debug logs for phylo in production, let
alone some that runs within pure code.

Debug logs will hinder performance, and showing them on the production
server is not their place anyway.

This commit correctly propagates the correct `LogConfig` in all the
places where we were just defaulting to log everything, and this allows
us to silence debug logs in tests, unless we want them.

Furthermore, the env var we used to override (in some parts) the logging
level from `LOG_LEVEL`  to `GGTX_LOG_LEVEL`, to avoid the env var
`LOG_LEVEL` clashing with some other service.

This will eventually allow us to properly override the logging level in
the tests, silencing non interesting stuff.

This will allow us to find all the use site of this function, trying to
see if we can use only `withLogger` or correctly control the logging
verbosity via the `HasLogger` and `LogInitParams`.