refactor(skills): rename multi-agent-* + agent-sessions-monitor + delegate-job to tmux-agent-orchestrate-*

Renamed 6 skills directories to tmux-agent-orchestrate-* prefix:
- multi-agent-create → tmux-agent-orchestrate-create
- multi-agent-resume → tmux-agent-orchestrate-resume
- multi-agent-delete → tmux-agent-orchestrate-delete
- multi-agent-status → tmux-agent-orchestrate-status
- agent-sessions-monitor → tmux-agent-orchestrate-monitor
- delegate-job → tmux-agent-orchestrate-delegate-job

Updated:
- skills/lib.sh internal paths (delegate_submit_job etc.)
- skills/tmux-agent-orchestrate-status/scripts/status.sh (monitor path)
- skills/tmux-agent-orchestrate-monitor/scripts/reconcile.sh
- .gitignore (HTML ignore patterns)
- 6 SKILL.md frontmatter (name, related_skills, prereq_skills) and body
- All script headers and Korean comments

Notes:
- tmux session naming convention unchanged (<slug>-creator-<agent>) — workspace identifier based, kept for backward compatibility
- Existing 2 sessions in -L multi-agent-canary untouched
- YAML delegate_job_id / agent-session (tmux:canary-...) preserved for log history compatibility

Verified on isolated server -L agy-rename-test (kill-server after).

.gitignore

@@ -14,5 +14,5 @@ __pycache__/
 *.pyc
 
 # 빌드/배포 HTML 산출물
-skills/delegate-job/USER_MANUAL.html
-skills/delegate-job/mqtt-broker-setup.html
+skills/tmux-agent-orchestrate-delegate-job/USER_MANUAL.html
+skills/tmux-agent-orchestrate-delegate-job/mqtt-broker-setup.html