Match the worker unit's User to the installed one

The socket is /tmp/tmux-$UID, so orchestra-tmux.service and
orchestra-worker.service must run as the same user or the worker talks to a
different server. The installed unit has run as kami since before the split;
the repo copy still said orchestra.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011xsXyr5J1RACo71YeKG3Pu

deploy/orchestra-worker.service

@@ -10,7 +10,7 @@ Wants=orchestra-tmux.service
 
 [Service]
 Type=simple
-User=orchestra
+User=kami
 EnvironmentFile=/etc/orchestra/worker.env
 ExecStart=/usr/local/bin/orchestra-worker
 Restart=always