This is the result of Autumn workshop 2024

sendNonblocking threw an error initially. I just do a compromise and
timeout the normal send (which blocks infinitely sometimes)

It's set up in user settings instead and has been for a long time.

Previously we would fail with a generic message suggesting to run
`gargantext-init`, but that wouldn't always be the case; sometimes
there might be problems connecting to the database, and we want to
show the raw exception. This code should help diagnosing what's wrong.

It also changes the error hint to report the correct executable, as
these days we use `gargantext-cli init` instead.

For some reason the default language (namely EN) was ignored when reading
the configuration file. After discussion with anoe, it appears that
this exclusion happens for historical reasons, so this commit removes it.

Now everything is in Core/Config