Pasture: Owncast 0.3.0

Owncast joins the pasture with federation turned on through its admin API; scenarios/owncast.sh has alice follow the
stream, receive its admin's message, like and boost it (both show in Owncast's admin), and unfollow: 13 checks, with
no change to PrivaPub.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw

tools/pasture/Caddyfile

@@ -108,6 +108,11 @@ nodebb.test {
 	reverse_proxy pasture-nodebb:4567
 }
 
+owncast.test {
+	tls internal
+	reverse_proxy pasture-owncast:8080
+}
+
 writefreely.test {
 	tls internal
 	reverse_proxy pasture-writefreely:8080