feat: add hidden tag to hide hosts from TUI and search

Hosts tagged with "hidden" are excluded from the TUI list, shell
completions, and sshm search. Direct connections via sshm <host>
still work regardless of the tag.

A toggle key (H) shows or hides hidden hosts in the TUI, with a
yellow banner indicating the active state. The key is documented
in the help panel (h).

A contextual hint on the Tags field in the add and edit forms
reminds the user that "hidden" hides the host from the list.

internal/config/ssh.go

@@ -1624,6 +1624,27 @@ func GetAllConfigFiles() ([]string, error) {
 	return files, nil
 }
 
+// FilterVisibleHosts returns only hosts that do not have the "hidden" tag.
+func FilterVisibleHosts(hosts []SSHHost) []SSHHost {
+	var visible []SSHHost
+	for _, h := range hosts {
+		if !hostHasTag(h.Tags, "hidden") {
+			visible = append(visible, h)
+		}
+	}
+	return visible
+}
+
+// hostHasTag reports whether the given tag list contains the target tag (case-insensitive).
+func hostHasTag(tags []string, target string) bool {
+	for _, t := range tags {
+		if strings.EqualFold(t, target) {
+			return true
+		}
+	}
+	return false
+}
+
 // GetAllConfigFilesFromBase returns all SSH config files starting from a specific base config file
 func GetAllConfigFilesFromBase(baseConfigPath string) ([]string, error) {
 	if baseConfigPath == "" {

internal/ui/add_form.go

@@ -438,7 +438,12 @@ func (m *addFormModel) renderGeneralTab() string {
 		b.WriteString(fieldStyle.Render(field.label))
 		b.WriteString("\n")
 		b.WriteString(m.inputs[field.index].View())
-		b.WriteString("\n\n")
+		b.WriteString("\n")
+		if field.index == tagsInput && m.focused == tagsInput {
+			b.WriteString(m.styles.FormHelp.Render(`  tip: use "hidden" to hide this host from the list`))
+			b.WriteString("\n")
+		}
+		b.WriteString("\n")
 	}
 
 	return b.String()

internal/ui/edit_form.go

@@ -599,7 +599,12 @@ func (m *editFormModel) renderEditGeneralTab() string {
 		b.WriteString(fieldStyle.Render(field.label))
 		b.WriteString("\n")
 		b.WriteString(m.inputs[field.index].View())
-		b.WriteString("\n\n")
+		b.WriteString("\n")
+		if field.index == 7 && m.focusArea == focusAreaProperties && m.focused == 7 {
+			b.WriteString(m.styles.FormHelp.Render(`  tip: use "hidden" to hide this host from the list`))
+			b.WriteString("\n")
+		}
+		b.WriteString("\n")
 	}
 
 	return b.String()

internal/ui/help_form.go

@@ -81,6 +81,9 @@ func (m *helpModel) View() string {
 		lipgloss.JoinHorizontal(lipgloss.Left,
 			m.styles.FocusedLabel.Render("p  "),
 			m.styles.HelpText.Render("ping all hosts")),
+		lipgloss.JoinHorizontal(lipgloss.Left,
+			m.styles.FocusedLabel.Render("H  "),
+			m.styles.HelpText.Render("toggle hidden hosts visibility")),
 		lipgloss.JoinHorizontal(lipgloss.Left,
 			m.styles.FocusedLabel.Render("f  "),
 			m.styles.HelpText.Render("setup port forwarding")),

internal/ui/model.go

@@ -70,8 +70,10 @@ func (p PortForwardType) String() string {
 type Model struct {
 	table          table.Model
 	searchInput    textinput.Model
-	hosts          []config.SSHHost
+	allHosts       []config.SSHHost // all parsed hosts, including hidden ones
+	hosts          []config.SSHHost // visible hosts (filtered by showHidden)
 	filteredHosts  []config.SSHHost
+	showHidden     bool // when true, hidden-tagged hosts are shown
 	searchMode     bool
 	deleteMode     bool
 	deleteHost     *config.SSHHost // Host to be deleted (with line number for precise targeting)
@@ -108,6 +110,14 @@ type Model struct {
 	showingError bool
 }
 
+// applyVisibilityFilter returns hosts filtered according to the showHidden flag.
+func (m Model) applyVisibilityFilter(hosts []config.SSHHost) []config.SSHHost {
+	if m.showHidden {
+		return hosts
+	}
+	return config.FilterVisibleHosts(hosts)
+}
+
 // updateTableStyles updates the table header border color based on focus state
 func (m *Model) updateTableStyles() {
 	s := table.DefaultStyles()

internal/ui/tui.go

@@ -48,7 +48,7 @@ func NewModel(hosts []config.SSHHost, configFile string, searchMode bool, curren
 
 	// Create the model with default sorting by name
 	m := Model{
-		hosts:          hosts,
+		allHosts:       hosts,
 		historyManager: historyManager,
 		pingManager:    pingManager,
 		sortMode:       SortByName,
@@ -63,8 +63,12 @@ func NewModel(hosts []config.SSHHost, configFile string, searchMode bool, curren
 		searchMode:     searchMode,
 	}
 
+	// Apply visibility filter (showHidden is false by default)
+	visibleHosts := m.applyVisibilityFilter(hosts)
+	m.hosts = visibleHosts
+
 	// Sort hosts according to the default sort mode
-	sortedHosts := m.sortHosts(hosts)
+	sortedHosts := m.sortHosts(visibleHosts)
 
 	// Create the search input
 	ti := textinput.New()

internal/ui/update.go

@@ -187,7 +187,8 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			if err != nil {
 				return m, tea.Quit
 			}
-			m.hosts = m.sortHosts(hosts)
+			m.allHosts = hosts
+			m.hosts = m.sortHosts(m.applyVisibilityFilter(hosts))
 
 			// Reapply search filter if there is one active
 			if m.searchInput.Value() != "" {
@@ -231,7 +232,8 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			if err != nil {
 				return m, tea.Quit
 			}
-			m.hosts = m.sortHosts(hosts)
+			m.allHosts = hosts
+			m.hosts = m.sortHosts(m.applyVisibilityFilter(hosts))
 
 			// Reapply search filter if there is one active
 			if m.searchInput.Value() != "" {
@@ -276,7 +278,8 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			if err != nil {
 				return m, tea.Quit
 			}
-			m.hosts = m.sortHosts(hosts)
+			m.allHosts = hosts
+			m.hosts = m.sortHosts(m.applyVisibilityFilter(hosts))
 
 			// Reapply search filter if there is one active
 			if m.searchInput.Value() != "" {
@@ -535,7 +538,8 @@ func (m Model) handleListViewKeys(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
 				m.table.Focus()
 				return m, nil
 			}
-			m.hosts = m.sortHosts(hosts)
+			m.allHosts = hosts
+			m.hosts = m.sortHosts(m.applyVisibilityFilter(hosts))
 
 			// Reapply search filter if there is one active
 			if m.searchInput.Value() != "" {
@@ -705,6 +709,19 @@ func (m Model) handleListViewKeys(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
 			m.viewMode = ViewHelp
 			return m, nil
 		}
+	case "H":
+		if !m.searchMode && !m.deleteMode {
+			// Toggle visibility of hidden hosts
+			m.showHidden = !m.showHidden
+			m.hosts = m.sortHosts(m.applyVisibilityFilter(m.allHosts))
+			if m.searchInput.Value() != "" {
+				m.filteredHosts = m.filterHosts(m.searchInput.Value())
+			} else {
+				m.filteredHosts = m.hosts
+			}
+			m.updateTableRows()
+			return m, nil
+		}
 	case "s":
 		if !m.searchMode && !m.deleteMode {
 			// Cycle through sort modes (only 2 modes now)

internal/ui/view.go

@@ -86,6 +86,14 @@ func (m Model) renderListView() string {
 		components = append(components, errorStyle.Render("❌ "+m.errorMessage))
 	}
 
+	// Add indicator when hidden hosts are shown
+	if m.showHidden {
+		hiddenBannerStyle := lipgloss.NewStyle().
+			Foreground(lipgloss.Color("11")).
+			Bold(true)
+		components = append(components, hiddenBannerStyle.Render("  [showing hidden hosts — press H to hide]"))
+	}
+
 	// Add the search bar with the appropriate style based on focus
 	searchPrompt := "Search (/ to focus): "
 	if m.searchMode {