fix(attach): hints print the row's attach_command (Issue #72, comments 926/930, U1)

create's closing hint, the delegate-job wrapper's dispatch hint and stop's
stuck-TUI message printed the pre-#71 forms (`herdr session attach <name>`,
`HERDR_SESSION_NAME=... herdr agent attach <name>`), which miss an agent whose
name is over 32 characters or has upper case. They now print the session row's
attach_command, or lib_py.agents.sanitize.attach_command(server, name) when
there is no row (lib.sh session_attach_command). deploy/INSTALL.md and
install_mam.sh show the `herdr --session <server> agent attach <herdr name>`
form.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

deploy/INSTALL.md

@@ -60,7 +60,7 @@ $ bash .agents/skills/multi-agent-mux-create/scripts/create_session.sh \
 ### 2) 세션 접속 (Attach)
 백그라운드에서 구동된 에이전트 TUI 화면에 들어갑니다.
 ```bash
-$ herdr session attach my-project-dev-claude
+$ herdr --session multi-agent-mux agent attach my-project-dev-claude
 ```
 *   **화면 탈출**: 대화 중 세션을 유지한 채 터미널로 돌아오려면 `Ctrl + B`를 누른 뒤 `D` 키를 차례로 입력합니다.
 

deploy/install_mam.sh

@@ -327,7 +327,7 @@ cat <<EOF
          --herdr-server multi-agent-mux
 
   2. Attach to the running session:
-     $ HERDR_SERVER_NAME=multi-agent-mux herdr agent attach <session_name>
+     $ herdr --session multi-agent-mux agent attach <herdr name>
 
   3. Gracefully stop the session:
      $ bash .agents/skills/multi-agent-mux-stop/scripts/stop_session.sh \\