When no intercept mode is selected by flag or config, a new
installation on macOS or a Windows desktop edition now uses "dns".
Windows Server, iOS and other platforms keep interface DNS mode unless
intercept is selected explicitly, and so does a config that cannot run
in intercept mode.
Existing Standard installations are not switched on upgrade. ctrld
start marks the services it installs fresh, and the service applies
the default below service.intercept_mode against the config it
fetches, so a service with neither a mode nor the marker predates the
default and keeps interface DNS mode, whichever path upgrades it; the
macOS package also pins such a service to "off" explicitly. An
explicit "off" stays final and is persisted.
Without reading the documentation, users may think that "ctrld start"
will just start ctrld service. However, this is not the case, and may
lead to unexpected result from user's point of view.
This commit changes "ctrld start" to just start already installed ctrld
service, so users won't lost what they did installed before. If there
are any arguments specified, performing the current behavior.
Since go1.21, Go standard library have added support for QUIC protocol.
The binary size gains between quic and quic-free version is now minimal.
Removing the quic free build, simplify the code and build process.
Using the same approach as in cd mode, but do it only once when running
ctrld the first time, then the config will be re-used then.
While at it, also adding Dockerfile.debug for better troubleshooting
with alpine base image.
When running on routers, ctrld leverages default setup, let dnsmasq runs
on port 53, and forward queries to ctrld listener on port 5354. However,
this setup is not serialized to config file, causing confusion to users.
Fixing this by writing the correct routers setup to config file. While
at it, updating documentation to refelct that, and also adding note that
changing default router setup could break things.
Cuong Manh Le