refactor: rename resolve_herdr_workspace to resolve_herdr_session and use herdr_session database field consistently

.agents/skills/multi-agent-mux-monitor/scripts/reconcile.sh

@@ -121,7 +121,7 @@ _changed = False
 for s in d.get('herdr_sessions', []):
     if s.get('delegate_job_id') == _jid and s.get('status') == 'running':
         _name = s.get('name')
-        _srv = s.get('herdr_workspace') or s.get('herdr_server') or 'default'
+        _srv = s.get('herdr_session') or s.get('herdr_workspace') or s.get('herdr_server') or 'default'
         if _event == 'completed':
             s['delegate_job_id'] = None
             print('MQTT Monitor: job completed on ' + str(_name) + ' — session kept alive', flush=True)
@@ -345,7 +345,7 @@ unique_servers = {'default'}
 if 'HERDR_SERVER_NAME' in os.environ:
     unique_servers.add(os.environ['HERDR_SERVER_NAME'])
 for s in d.get('herdr_sessions', []):
-    srv = s.get('herdr_workspace') or s.get('herdr_server') or 'default'
+    srv = s.get('herdr_session') or s.get('herdr_workspace') or s.get('herdr_server') or 'default'
     unique_servers.add(srv)
 
 try:
@@ -399,7 +399,7 @@ if herdr_confirmed:
         # (없으면 herdr-dead stopped 세션을 'terminated' 로 덮어써 resumable 플래그가 소실됨)
         if s.get('status') in ('terminated', 'archived', 'stopped'):
             continue
-        srv = s.get('herdr_workspace') or s.get('herdr_server') or 'default'
+        srv = s.get('herdr_session') or s.get('herdr_workspace') or s.get('herdr_server') or 'default'
         if (name, srv) not in alive_set:
             s['status'] = 'terminated'
             s['terminated_at'] = now_iso