fix: seven fixes — token scan, variadic cleanup, TUI layout, compose secrets

1. UpdateSite handles token-read Scan error instead of ignoring it.
   sql.ErrNoRows (nonexistent site) passes through; real DB errors
   surface.

2. RunCheck allowPrivate changed from variadic to real bool param.
   Dead maxRequestBody duplicate removed from sqlstore.go.

3. Footer help bar documents [Space] for group collapse.

4. adjustCursor unified with clampCursor — one clamping path
   instead of two with different semantics.

5. Compose cluster/probe example files annotate hardcoded secrets
   with "EXAMPLE ONLY — rotate before use".

6. huhForm.WithHeight moved from View() to handleResize — no longer
   mutates form state during render.

7. maxTableRows recalculated on filter enter/exit via recalcLayout()
   — was only recalculated on resize, causing off-by-one when the
   filter bar appeared/disappeared.

internal/tui/view_dashboard.go

@@ -85,11 +85,6 @@ func (m Model) View() string {
 			case stateFormMaint:
 				title = "New Maintenance Window"
 			}
-			formHeight := m.termHeight - 7
-			if formHeight < 5 {
-				formHeight = 5
-			}
-			m.huhForm.WithHeight(formHeight)
 			header := m.st.titleStyle.Render(title)
 			footer := m.st.subtleStyle.Render("\n[Esc] Cancel")
 			return lipgloss.NewStyle().Padding(1, 2).Render(header + "\n\n" + m.huhForm.View() + "\n" + footer)
@@ -270,7 +265,7 @@ func (m Model) renderFooter(stats dashboardStats) string {
 	var keys string
 	switch m.currentTab {
 	case 0:
-		keys = "[/]Filter [n]New [e]Edit [i]Info [d]Del [p]Pause [T]Theme [Tab]Switch [q]Quit"
+		keys = "[/]Filter [n]New [e]Edit [i]Info [d]Del [p]Pause [Space]Collapse [T]Theme [Tab]Switch [q]Quit"
 	case 1:
 		keys = "[n]New [e]Edit [i]Info [d]Del [t]Test [T]Theme [Tab]Switch [q]Quit"
 	case 2: