Parse newly added Snowflake statistics lines
As cohosh writes in legacy/trac#31157 (moved), Snowflake statistics files will soon contain new lines:
diff --git a/doc/broker-spec.txt b/doc/broker-spec.txt
index 2877784..eba3347 100644
--- a/doc/broker-spec.txt
+++ b/doc/broker-spec.txt
@@ -31,6 +31,24 @@ Metrics data from the Snowflake broker can be retrieved by sending an HTTP GET r
A count of the total number of unique IP addresses of Snowflake
proxies that have polled.
+ "snowflake-ips-standalone" NUM NL
+ [At most once.]
+
+ A count of the total number of unique IP addresses of snowflake
+ proxies of type "standalone" that have polled.
+
+ "snowflake-ips-badge" NUM NL
+ [At most once.]
+
+ A count of the total number of unique IP addresses of snowflake
+ proxies of type "badge" that have polled.
+
+ "snowflake-ips-webext" NUM NL
+ [At most once.]
+
+ A count of the total number of unique IP addresses of snowflake
+ proxies of type "webext" that have polled.
+
"snowflake-idle-count" NUM NL
[At most once.]
Let's parse these new lines in metrics-lib as soon as files containing them exist on CollecTor.