fix: serialize target panel operations

internal/tui/model.go

@@ -72,8 +72,18 @@ func NewModel(application app.Module) Model {
 
 func (m Model) Init() tea.Cmd { return nil }
 
+// busy is the single-operation guard for asynchronous Application work. Every
+// operation start checks it, so a completion can only belong to the one current
+// operation rather than racing another operation for shared model state.
+func (m Model) busy() bool {
+	return m.applying || m.refreshing || m.profileTransition || m.pendingActivation.Kind != 0
+}
+
 func (m Model) Update(message tea.Msg) (tea.Model, tea.Cmd) {
 	if completed, ok := message.(refreshDone); ok {
+		if !m.refreshing {
+			return m, nil
+		}
 		m.refreshing = false
 		m.snapshot = completed.result.Snapshot
 		if completed.result.Err != nil {
@@ -81,12 +91,20 @@ func (m Model) Update(message tea.Msg) (tea.Model, tea.Cmd) {
 		} else {
 			m.status = completed.result.Notice
 		}
-		if m.selected >= len(m.availableTargets()) && m.selected > 0 {
-			m.selected--
+		targetCount := len(m.availableTargets())
+		if targetCount == 0 {
+			m.selected = 0
+		} else if m.selected < 0 {
+			m.selected = 0
+		} else if m.selected >= targetCount {
+			m.selected = targetCount - 1
 		}
 		return m, nil
 	}
 	if progress, ok := message.(profileOperationProgress); ok {
+		if !m.profileTransition {
+			return m, nil
+		}
 		m.snapshot = progress.result.Snapshot
 		m.progressTarget = ""
 		if len(progress.result.Progress) > 0 {
@@ -119,6 +137,9 @@ func (m Model) Update(message tea.Msg) (tea.Model, tea.Cmd) {
 		return m, waitForProfileProgress(progress.updates)
 	}
 	if completed, ok := message.(targetOperationDone); ok {
+		if !m.applying || m.profileTransition {
+			return m, nil
+		}
 		m.applying = false
 		m.snapshot = completed.result.Snapshot
 		if completed.result.Confirmation != "" {
@@ -159,7 +180,7 @@ func (m Model) Update(message tea.Msg) (tea.Model, tea.Cmd) {
 }
 
 func (m Model) updateMain(key tea.KeyMsg) (tea.Model, tea.Cmd) {
-	if m.targetConfirm != nil && !m.applying {
+	if m.targetConfirm != nil && !m.busy() {
 		switch key.String() {
 		case "y":
 			intent := *m.targetConfirm
@@ -177,14 +198,18 @@ func (m Model) updateMain(key tea.KeyMsg) (tea.Model, tea.Cmd) {
 	targets := m.availableTargets()
 	switch key.String() {
 	case "p":
-		m.page = profilesPage
-		m.selected = 0
-		m.status = ""
+		if !m.busy() {
+			m.page = profilesPage
+			m.selected = 0
+			m.status = ""
+		}
 	case "?":
-		m.page = helpPage
-		m.status = ""
+		if !m.busy() {
+			m.page = helpPage
+			m.status = ""
+		}
 	case "r":
-		if !m.applying && !m.refreshing {
+		if !m.busy() {
 			m.refreshing = true
 			m.status = "Refreshing Target availability and state…"
 			return m, func() tea.Msg {
@@ -192,15 +217,15 @@ func (m Model) updateMain(key tea.KeyMsg) (tea.Model, tea.Cmd) {
 			}
 		}
 	case "up", "k":
-		if !m.applying && m.selected > 0 {
+		if !m.busy() && m.selected > 0 {
 			m.selected--
 		}
 	case "down", "j":
-		if !m.applying && m.selected+1 < len(targets) {
+		if !m.busy() && m.selected+1 < len(targets) {
 			m.selected++
 		}
 	case " ":
-		if !m.applying && m.selected >= 0 && m.selected < len(targets) {
+		if !m.busy() && m.selected >= 0 && m.selected < len(targets) {
 			selected := targets[m.selected]
 			desired := selected.State == target.Disabled || selected.State == target.External
 			m.applying = true
@@ -224,9 +249,11 @@ func (m Model) updateProfiles(key tea.KeyMsg) (tea.Model, tea.Cmd) {
 			intent := *m.profileConfirm
 			intent.Confirm = true
 			m.profileConfirm = nil
+			m.pendingActivation = app.Intent{}
 			return m.beginProfileActivation(intent)
 		case "n", "esc", "q":
 			m.profileConfirm = nil
+			m.pendingActivation = app.Intent{}
 			m.status = ""
 		}
 		return m, nil
@@ -243,6 +270,14 @@ func (m Model) updateProfiles(key tea.KeyMsg) (tea.Model, tea.Cmd) {
 		}
 		return m, nil
 	}
+	if m.busy() {
+		if key.String() == "q" || key.String() == "esc" {
+			m.page = mainPage
+			m.selected = 0
+			m.status = ""
+		}
+		return m, nil
+	}
 
 	switch key.String() {
 	case "q", "esc":
@@ -332,6 +367,9 @@ func (m Model) updateForm(key tea.KeyMsg) (tea.Model, tea.Cmd) {
 }
 
 func (m Model) beginProfileActivation(intent app.Intent) (tea.Model, tea.Cmd) {
+	if m.busy() {
+		return m, nil
+	}
 	if progressive, ok := m.application.(app.ProgressiveModule); ok {
 		m.applying = true
 		m.profileTransition = true