Summary:
# get debug output (for the plugin and the called servers)
export LSPCLIENT_DEBUG=1

At the moment the plugin is "very" verbose and just setting
QT_LOGGING_RULES in the env isn't enough as you need to e.g.
alter the clangd start command

I propose the env var to let people handle this,
we can use the m_debugMode for starting other LSP servers
in verbose/non-verbose mode later, too

Reviewers: mnauwelaerts, dhaumann

Reviewed By: mnauwelaerts

Subscribers: kwrite-devel

Tags: #kate

Differential Revision: https://phabricator.kde.org/D22633