Add config options to coarsely disable log/tracing without initialization.

Signed-off-by: Jason Volk <jason@zemos.net>

tuwunel-example.toml

@@ -751,6 +751,22 @@
 #
 #log_to_stderr = false
 
+# Setting to false disables the logging/tracing system at a lower level.
+# In contrast to configuring an empty `log` string where the system is
+# still operating but muted, when this option is false the system was not
+# initialized and is not operating. Changing this option has no effect
+# after startup. This option is intended for developers and expert use
+# only: configuring an empty log string is preferred over using this.
+#
+#log_enable = true
+
+# Setting to false disables the logging/tracing system at a lower level
+# similar to `log_enable`. In this case the system is configured normally,
+# but not registered as the global handler in the final steps. This option
+# is for developers and expert use only.
+#
+#log_global_default = true
+
 # OpenID token expiration/TTL in seconds.
 #
 # These are the OpenID tokens that are primarily used for Matrix account