chore(release): irtt-server 0.5.1, irtt-rs 0.6.1

irtt-server gains address_family_available() as a public helper, and
irtt-rs picks up the server zero-argument defaults and single-family
fallback that depend on it.

Cargo.lock

@@ -749,7 +749,7 @@ dependencies = [
 
 [[package]]
 name = "irtt-rs"
-version = "0.6.0"
+version = "0.6.1"
 dependencies = [
  "clap",
  "crossterm",
@@ -764,7 +764,7 @@ dependencies = [
 
 [[package]]
 name = "irtt-server"
-version = "0.5.0"
+version = "0.5.1"
 dependencies = [
  "getrandom 0.4.3",
  "irtt-proto",