TUI: remove service mutation actions from pane menu

[edwin-zvs]

Summary

• remove edit, HTTP token rotation, and pause/resume items from the service pane title menu
• keep only split, close, and delete pane actions and their key hints
• update the service-view UX spec and add a focused rendering test

Verification

• cargo build ✅
• cargo test -p construct-cli service_view_title_menu_shows_only_pane_actions ✅
• cargo test -p construct-cli ⚠️ 1326 passed; 2 unrelated existing failures: color::tests::truecolor_backend_still_emits_rgb and pty_render::tests::smith_tool_expand_collapse_rebuilds_only_retained_suffix