feat: clear screen on SSH enter/exit, host list scrolling, 'e' edit key

- tea.Batch(tea.ClearScreen, sshConnectCmd) before SSH starts so TUI
  output doesn't bleed into SSH terminal
- tea.ClearScreen after SSH exits so SSH output doesn't ghost in TUI
- Host list now paginates: only (term_height - 8) / 5 cards shown,
  viewport follows selectedIndex with centered scrolling
- Shows 'N of M hosts' indicator when content is clipped
- Added 'e' key alias for editing host (Ctrl+E or E)

pkg/tui/host_list_tab.go

@@ -68,7 +68,7 @@ func (t *HostListTab) Update(msg tea.Msg) (Tab, tea.Cmd) {
 				return openHostFormMsg{}
 			}
 
-		case "ctrl+e":
+		case "ctrl+e", "e":
 			if len(t.hosts) > 0 {
 				host := t.hosts[t.selectedIndex]
 				return t, func() tea.Msg {
@@ -139,15 +139,39 @@ func (t *HostListTab) View() string {
 		b.WriteString(centerText(SubtitleStyle.Render("No hosts found. Add with Ctrl+N"), availW))
 		b.WriteString("\n")
 	} else {
-		for i, host := range t.hosts {
+		// Scrolling: show only what fits on screen
+		cardH := 5 // 4 lines per card + 1 blank separator
+		maxCards := (t.height - 8) / cardH
+		if maxCards < 1 {
+			maxCards = 1
+		}
+		if maxCards > len(t.hosts) {
+			maxCards = len(t.hosts)
+		}
+
+		start := t.selectedIndex - maxCards/2
+		if start < 0 {
+			start = 0
+		}
+		if start+maxCards > len(t.hosts) {
+			start = len(t.hosts) - maxCards
+		}
+
+		for i := start; i < start+maxCards; i++ {
+			host := t.hosts[i]
 			entry := renderHostEntry(host, i == t.selectedIndex, cardW)
-			// Center the card (which produces 4 lines) horizontally
 			for _, line := range strings.Split(entry, "\n") {
 				b.WriteString(centerText(line, availW))
 				b.WriteString("\n")
 			}
 			b.WriteString("\n")
 		}
+
+		if maxCards < len(t.hosts) {
+			b.WriteString(centerText(
+				SubtitleStyle.Render(fmt.Sprintf("%d of %d hosts", start+1, len(t.hosts))),
+				availW))
+		}
 	}
 
 	return b.String()

pkg/tui/tui.go

@@ -62,13 +62,13 @@ func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		return m, tea.Quit
 
 	case sshConnectToMsg:
-		return m, sshConnectCmd(msg.host, m.dataDir)
+		return m, tea.Batch(tea.ClearScreen, sshConnectCmd(msg.host, m.dataDir))
 
 	case sshExitMsg:
 		if msg.err != nil {
 			m.Error = msg.err
 		}
-		return m, nil
+		return m, tea.ClearScreen
 
 	case openHostFormMsg:
 		var tab Tab