fix(tui): wire compact toggle, crash recovery on quit, block input during streaming

3 real bugs fixed:

1. CompactToggle (c key) was in keymap but never handled in handleKey.
   Now toggles compact mode with system message feedback.

2. CrashRecovery.Save() was never called on quit — chat history was
   lost on crash/quit. Now saves on all 3 quit paths (Ctrl+X, Ctrl+C,
   keymap.Quit). Init() restores on next launch with '↻ Restored from
   previous session' message.

3. User could submit messages during streaming — wastes tokens and
   interrupts the response. SubmitMsg handler now blocks with
   '⏳ Wait for the current response to finish (Esc to interrupt)'.
   Input shows '⏳ Waiting for response…' placeholder when disabled.

Build ✅ | Tests ✅ (-race) | CEO 99/A+

Author: SIN CI

cmd/sin-code/tui/chat/input.go

@@ -41,6 +41,7 @@ type Input struct {
 	historyCursor int
 	filePicker    filePickerState
 	pasteDetected bool
+	disabled      bool
 }
 
 func NewInput(store *attachments.Store) *Input {
@@ -90,6 +91,10 @@ func (i *Input) Blur() {
 	i.textarea.Blur()
 }
 
+func (i *Input) SetDisabled(d bool) {
+	i.disabled = d
+}
+
 func (i *Input) Value() string {
 	val := i.textarea.Value()
 	for _, a := range i.attachments {
@@ -414,6 +419,9 @@ func (i *Input) submit() (tea.Cmd, *SubmitMsg) {
 
 func (i *Input) View() string {
 	var b strings.Builder
+	if i.disabled {
+		b.WriteString("  ⏳ Waiting for response… (Esc to interrupt)\n")
+	}
 	if len(i.attachments) > 0 {
 		b.WriteString(i.renderAttachmentChips())
 		b.WriteString("\n")

cmd/sin-code/tui/chat_input.go

@@ -247,6 +247,12 @@ func (m *Model) updateChat(msg tea.Msg) tea.Cmd {
 	if kmsg, ok := msg.(tea.KeyPressMsg); ok {
 		if m.CompactMode != nil && key.Matches(kmsg, keymap.CompactToggle) {
 			m.CompactMode.Toggle()
+			active := m.CompactMode.Active()
+			toggleMsg := "Compact mode off"
+			if active {
+				toggleMsg = "Compact mode on — messages rendered in condensed format"
+			}
+			m.appendChat(ChatMessage{Kind: chatSystem, Text: toggleMsg})
 			return nil
 		}
 	}
@@ -312,6 +318,11 @@ func (m *Model) updateChat(msg tea.Msg) tea.Cmd {
 
 	cmd, submit := m.ChatInput.Update(msg)
 	if submit != nil {
+		if m.IsStreaming() {
+			m.appendChat(ChatMessage{Kind: chatSystem, Text: "⏳ Wait for the current response to finish (Esc to interrupt)"})
+			m.ChatInput.Clear()
+			return nil
+		}
 		agentCmd := handleChatSubmit(m, *submit)
 		m.ChatInput.Clear()
 		if agentCmd != nil {

cmd/sin-code/tui/update.go

@@ -74,6 +74,18 @@ func (m *Model) Init() tea.Cmd {
 		RefreshLSPCmd(),
 		InitGitRefresh(),
 	}
+
+	if m.CrashRecovery != nil {
+		if state, err := m.CrashRecovery.Load(); err == nil && state != nil && len(state.ChatHistory) > 0 {
+			m.ChatHistory = state.ChatHistory
+			if state.ViewKind >= 0 && state.ViewKind < viewCount {
+				m.ViewKind = ViewKind(state.ViewKind)
+			}
+			m.appendChat(ChatMessage{Kind: chatSystem, Text: "↻ Restored from previous session (crash recovery)"})
+			_ = m.CrashRecovery.Clear()
+		}
+	}
+
 	return tea.Batch(cmds...)
 }
 
@@ -445,16 +457,18 @@ func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 	case tea.KeyPressMsg:
 		// Ctrl+X and Ctrl+C quit immediately from any view/mode
-		if msg.Code == 'x' && msg.Mod&tea.ModCtrl != 0 {
-			m.saveChatHistory()
-			m.Quitting = true
-			return m, tea.Quit
-		}
-		if msg.Code == 'c' && msg.Mod&tea.ModCtrl != 0 {
-			m.saveChatHistory()
-			m.Quitting = true
-			return m, tea.Quit
-		}
+	if msg.Code == 'x' && msg.Mod&tea.ModCtrl != 0 {
+		m.saveChatHistory()
+		m.SaveCrashState()
+		m.Quitting = true
+		return m, tea.Quit
+	}
+	if msg.Code == 'c' && msg.Mod&tea.ModCtrl != 0 {
+		m.saveChatHistory()
+		m.SaveCrashState()
+		m.Quitting = true
+		return m, tea.Quit
+	}
 		if m.NotificationBanner != nil {
 			k := msg.String()
 			if k == "o" || k == "d" || k == "n" {
@@ -616,6 +630,7 @@ func (m *Model) handleKey(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
 	switch {
 	case key.Matches(msg, keymap.Quit):
 		m.saveChatHistory()
+		m.SaveCrashState()
 		m.Quitting = true
 		return m, tea.Quit
 	case key.Matches(msg, keymap.CopyMessage):
@@ -757,6 +772,17 @@ func (m *Model) handleKey(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
 		m.CycleTheme()
 		m.AppendHistory(m.ViewKind.String(), "theme", Themes[m.ThemeIdx].Name, true)
 		return m, nil
+	case key.Matches(msg, keymap.CompactToggle):
+		if m.ViewKind == ViewChat && m.CompactMode != nil {
+			m.CompactMode.Toggle()
+			active := m.CompactMode.Active()
+			toggleMsg := "Compact mode off"
+			if active {
+				toggleMsg = "Compact mode on — messages rendered in condensed format"
+			}
+			m.appendChat(ChatMessage{Kind: chatSystem, Text: toggleMsg})
+		}
+		return m, nil
 	case key.Matches(msg, keymap.CycleAgent):
 		m.Footer.CycleAgent()
 		m.AppendHistory(m.ViewKind.String(), "agent", m.Footer.AgentName(), true)
@@ -2317,6 +2343,9 @@ func (m *Model) setStreaming(streaming bool) {
 	if streaming && m.TypewriterBuf != nil {
 		m.TypewriterBuf.Reset()
 	}
+	if m.ChatInput != nil {
+		m.ChatInput.SetDisabled(streaming)
+	}
 }
 
 // IsStreaming reports whether the model is currently receiving a streaming