Release on GitHub

Added

• Three-mode window system: OS decorated, borderless windowed, fullscreen - all with custom titlebar in non-OS modes
• Per-pane titlebar buttons: minimize, position-swap (shows popup to swap with another pane), type-swap (changes pane type), settings, close
• Sidebar pane rows with full action button set matching the titlebar
• Bottom status bar showing active pane info, FPS/ms, and window mode indicator
• “Show titlebar” toggle in Settings → System to hide per-pane titlebars
• Window mode dropdown in sidebar and Settings panel, synced via shared WINDOW_MODE_LABELS
• Auto-spawn one terminal on first launch (no saved layout)
• Workspace Trust dialog: warns before restoring layouts saved with a different shell

Changed

• System tab moved to first position in Settings panel
• Window mode dropdown labels unified to “OS” / “Windowed” / “Windowless”
• FPS/metrics moved from sidebar to bottom status bar
• Sidebar “Add Pane” dropdown replaced with 4 icon buttons per pane type + “+16” bulk spawn via command palette
• Titlebar mode-toggle button removed; mode switching via sidebar/settings dropdown only
• _toggle_borderless shortcut (Ctrl+Shift+F11) and _toggle_custom_window_mode removed

Fixed

• Layout persistence: save on _exit_tree() instead of unreliable WM_CLOSE_REQUEST
• Window mode persisted correctly on restart (was silently defaulting to 0)
• Settings persisted on exit (were not saved in _exit_tree)
• Window mode application order: always reset to WINDOW_MODE_WINDOWED before applying target mode
• Titlebar Phosphor icon rendering via Label child nodes
• Profile trust dialog no longer shows redundant “replace layout?” confirmation
• as keyword renamed to adj_saved in terminal_manager.gd
• Titlebar drag-to-move: background and label mouse_filter set to IGNORE